Discrete Math Seminars

Wednesdays 10:30-11:30AM (PDT) on Zoom

Please join us for this weekly seminar on a wide variety of topics under the umbrella of discrete mathematics. We gratefully acknowledge the Pacific Institute of Mathematical Sciences for their generous funding since 2010.

Unless otherwise noted, all talks take place on Wednesdays at 10:30am on Zoom ( Meeting-ID: 924 4402 9792). We welcome remote participation from groups at other universities.

All talks will be announced on this page, on the department calendar, and on the DM Seminar mailing list. If you have an SFU email address, you can subscribe or unsubscribe to the mailing list by logging in to maillist.sfu.ca and searching for the math-dmsem list. Otherwise, you can ask any discrete math faculty member to manually add you to the list. 

Current organizers: Kevin Halasz (email:  khalasz@sfu.ca), Alexandra Wesolek (agwesole@sfu.ca), and Danielle Rogers (djr8@sfu.ca)

Fall 2020

16 September Marthe Bonamy, LaBRI On Vizing's edge colouring question
In his 1965 seminal paper on edge colouring, Vizing proved that a (Delta+1)-edge colouring can be reached from any given proper edge colouring through a series of Kempe changes, where Delta is the maximum degree of the graph. He concludes the paper with the following question: can an optimal edge colouring be reached from any given proper edge colouring through a series of Kempe changes? In other words, if the graph is Delta-edge-colourable, can we always reach a Delta-edge-colouring? If true, this would imply a more recent conjecture of Mohar (2006) that in any graph, all (Delta+2)-edge-colourings are equivalent up to a series of Kempe changes. We discuss recent progress around these questions.
23 September Carla Groenland, University of Oxford Asymptotic dimension of graph classes
I will attempt to give some intuition for asymptotic dimension of graph classes, starting from the definition and giving the connection to clustered colouring and weak-diameter network decompositions. I will sketch the ideas behind some of our results, e.g. that the class of planar graphs has asymptotic dimension 2. Asymptotic dimension was introduced by Gromov in 1993 within geometric group theory and in the graph setting makes sense for infinite graphs or graph classes. Joint work with M. Bonamy, N. Bousquet, L. Esperet, F. Pirot, and A. Scott.
30 September Karen Yeats, University of Waterloo Chains of hourglasses and the graph theory of their Feynman integrals
I will give a set up for understanding the graph theory of Feynman integrals that I have been using over the last number of years. It is all very combinatorial and does not require any understanding of physics or analysis. Then I will explain about some joint work with Oliver Schnetz where we are able to complete a generalized denominator reduction on a particular family of graphs and from this calculate an arithmetic graph invariant on them known as the c_2 invariant as well as understand properties of their Feynman integrals.
7 October Shanise Walker, University of Wisconsin Eau Claire The Game of Cycles
The Game of Cycles was introduced by Francis Su in his book titled Mathematics for Human Flourishing (2020). The game is played on a simple connected planar graph together with its bounded cells, and players take turns marking edges with arrows according to a sink-source rule. The object of the game is to produce a cycle cell–a cell surrounded by arrows all cycling in one direction–or to make the last possible move. In this talk, we explore the two-player game for various classes of graphs and determine who has a winning strategy.
14 October Laura Escobar, Washington University in St. Louis Which Schubert varieties are Hessenberg varieties?
Schubert varieties are subvarieties of the flag variety whose geometry can be understood using the combinatorics of permutations. Hessenberg varieties are also subvarieties of the flag variety with connections to both algebraic combinatorics and representation theory. After introducing and motivating these varieties, I will discuss joint work with Martha Precup and John Shareshian in which we investigate which Schubert varieties in the full flag variety are Hessenberg varieties.
21 October Inês Rodrigues, University of Lisbon An action of the cactus group on the shifted tableau crystal
The shifted tableau crystal is a crystal-like structure on shifted semistandard tableaux, introduced by Gillespie, Levinson and Purboo (2017). We define on this structure a shifted version of the crystal reflection operators, originally introduced by Lascoux and Schützenberger on type A crystals, which coincide with the restrictions of the shifted Schützenberger involution on primed intervals of two adjacent letters. Unlike type A crystal they not yield an action of the symmetric group. Following a similar approach as Halacheva (2016), we then exhibit a natural action of the cactus group on the shifted tableau crystal, realized by the restrictions of the shifted Schützenberger involution to all primed intervals of the underlying crystal alphabet, including, in particular, the crystal reflection operators.
28 October Jana Novotná, University of Warsaw/Charles University Clique-width of Atoms and Coloring for Hereditary Graphs
Clique-width is a well-established graph parameter. Many NP-complete graph problems are polynomially solvable on graph classes of bounded clique-width. Moreover, several of these problems are polynomially solvable on a hereditary graph class G if they are so on the atoms (graphs with no clique cut-set) of G. For these reasons, the boundedness of clique-width has been investigated for many graph classes. In this talk, we consider graph classes defined by one or two forbidden induced subgraphs. We discuss the coloring problem and the boundedness of clique-width of their atoms.
4 November Karen Meagher, University of Regina Erdős–Ko–Rado Theorems for Groups

The first half of this talk will be a gentle introduction to the Erdős–Ko–Rado (EKR) Theorem. This is a theorem that determines the size and structure of the largest collection of intersecting sets. It has become a cornerstone of extremal set theory and has been extended to many other objects. I will show how this result can be proven using techniques from algebraic graph theory.

In the second half of this talk I will give more details about extensions of the EKR theorem to permutations. Two permutations are intersecting if they both map some i to the same point (so σ and π are intersecting if and only if σ−1π has a fixed point). In 1977, Deza and Frankl proved that the size of a set of intersecting permutations is at most (n-1)!. It wasn't until 2003 that the structure of sets of intersecting permutations that meet this bound was determined.

For any group action, we can ask what is the size and structure of the largest set of intersecting permutations. I will show some recent results for different groups, with a focus on 2-transitive groups.

12 November 2:30-3:20pm Patricia Hersh, University of Oregon Posets arising as 1-skeleta of simple polytopes, the nonrevisiting path conjecture, and poset topology
Held jointly with the SFU Operations Research Seminar Note the nonstandard time and day of the week
Abstract: Given a polytope P and a nonzero vector c, the question of which point in P has largest inner product (or smallest inner product) with c is the main goal of linear programming in operations research. Key to efficiency questions regarding linear programming is the directed graph G(P,c) on the 1-skeleton of P obtained by directing each edge e(u,v) from u to v for c(u) < c(v) and in particular the diameter of G(P,c). We will explore the question of finding sufficient conditions on P and c to guarantee that no directed path ever revisits any polytope face that it has left; this is enough to ensure that linear programming is efficient under all possible choices of pivot rule. It turns out that poset-theoretic techniques and poset topology can help shed light on this question. In discussing work on this question, we will provide background along the way.
18 November Natasha Morrison, University of Victoria Hypergraph Lagrangians: Extremal Combinatorics and the Frankl-Füredi conjecture
In this talk we explore the origins of hypergraph Lagrangians and their applications to classical problems in extremal combinatorics. We then focus on the Frankl-Füredi conjecture, which concerns the maximal value of the Lagrangian of an r-uniform hypergraph with m edges. In particular, we show that the conjecture is false in general, but holds for all sufficiently large 3-uniform hypergraphs. This talk is based on joint work with Vytautas Gruslys and Shoham Letzter.
25 November Amélie Trotignon, Johannes Kepler University Discrete harmonic functions in the three-quarter plane
Harmonic functions play an important role in probability theory and are strongly related to the enumeration of walks. Doob h-transform is a way to build conditioned random processes in cones from a random process and a positive harmonic function vanishing on the boundary of the cone. Finding positive harmonic functions for random processes is therefore a natural objective in the study of confined random walks. There are very few ways to compute discrete harmonic functions. In this talk we are interested in positive discrete harmonic functions with Dirichlet conditions in three quadrants. Whereas planar lattice (random) walks in the quadrant have been well studied, the case of walks avoiding a quadrant has been developed lately. We extend the method in the quarter plane – resolution of a functional equation via boundary value problem using a conformal mapping – to the three-quarter plane applying the strategy of splitting the domain into two symmetric convex cones. We obtain a simple explicit expression for the algebraic generating function of harmonic functions associated to random walks avoiding a quadrant.
2 December Sofiat Olaosebikan, University of Glashow TBA
9 December Aparna Lakshmanan, St. Xavier's College TBA

Spring 2020

  All the remaining sessions cancelled due to the coronavirus disease (COVID-19)  
10 March David Wood, Monash University Graph and Poset Dimension Parameters
3 March Alexander Pott, Otto von Guericke University Magdeburg Vanishing flats: a combinatorial viewpoint on the nonlinearity of functions
25  Feburary Mehdi Salimi, SFU Pursuit-Evasion Games
18 Feburary Jason Schoeters, University of Bordeaux Temporal cliques admit sparse spanners
11 Feburary Timothy Chan, Monash and Warwick Matroid branch-depth and integer programming
 4  Feburary (Cancelled due to campus snowfall closure)  
28 January 

Joris van der Hoeven, CNRS 

(Distinguished PIMS Discrete Math talk)

Integer multiplication in time O(n log n) 
21 January Joris van der Hoeven, CNRS Historic algorithms for integer multiplication

14  January

Kevin Halasz, SFU Near transversals of latin squares

2019 Talks

Fall 2019

03 December Stephanie van Willigenburg, UBC
The e-positivity of chromatic symmetric functions
26 November Peter Horak, University of Washington
Extremal problems on cycles in graphs
19 November Thaís Bardini, SFU
Fault tolerance in cryptographic applications using cover-free families
12 November Brin Chan, UBC
A generalization of balanced tableaux and matching problems with unique solutions
05 November Pavol Hell, SFU Graphs with possible loops
29 October Kathryn Nurse, SFU
Maximum Directed Linear Arrangement
22 October Robert Samal, Charles University
The binary paint shop problem (aka necklace splitting problem)
15 October Farid Aliniaeifard, UBC
Combinatorial Hopf algebras and representation theory
08 October Rikke Marie Langhede, DTU
The weak group connectivity number versus the group connectivity number
01 October Petr Lisonek, SFU
Maximally non-associative quasigroups
24 September Gary MacGillivray, University of Victoria
Switching (m,n)-edge-coloured graphs
17 September Gonzalez Hermosillo de la Maza, SFU
Active cops and robbers
10 September
Peter Bradshaw, SFU
Graphs with high cop number
03 September Curtis Bright, University of Waterloo
SAT Solving with Computer Algebra: A Powerful Combinatorial Search Method

Spring 2019

23 April Amarpreet Rattan, SFU Parking functions and factorizations of the full cycle.
16 April Igor Shinkar, SFU
On (almost) Lipschitz mappings on the discrete hypercube
9 April Peter Bradshaw, SFU Cops and Robbers on Cayley Graphs
2 April
Nike Dattani, Harvard-Smithsonian Center for Astrophysics Solving mathematical and machine learning problems on quantum computers
26 March
Peter Horak, University of Washington
Old and New Conjectures in Tilings
19 March Bojan Mohar, SFU Toward a Theory of Crossing-Critical Graphs, Part I

2018 Talks

Fall 2018

4 December
Michael Monagan, SFU How to factor a multivariate polynomial
20 November Mahdieh Malekian, SFU Excluding small graphs as immersion
13 November Bojan Mohar, SFU 50 Years of the Ringel-Youngs Map Colour Theorem
23 October Jonathan Jedwab, SFU New Constructions of Difference Matrices
16 October
Leionid Chindelevitch, SFU Metabolic networks: discrete geometry and optimization
9 October Matt DeVos, SFU On the colourful world of Ron Aharoni

Summer 2018

7 August Fuji Zhang Spectral dynamics of graph eigenvalues
31 July Sebastian Gonzalez, SFU  
10 July Yifan Jing, SFU On the genus of complete 3-uniform hypergraphs
26 June Andrew Berget, Western Washington U Internal Zonotopal Algebras of Reflection Arrangements
5 June Cedric Chauve, SFU MaxTiC, ranking species trees using network constraints
29 May Amy Wiebe, University of Washington The Slack Realization Space of a Polytope
22 May James Davis, University of Richmond Apple vs Samsung: a Mathematical Battle
15 May
Haiyan Chen On the sandpile group of a polygon flower

Spring 2018

12 April Jephian Lin The zero forcing process and the strong Arnold property
31 March, Seattle Sylvie Corteel, Kevin Purbhoo, Steph van Willigenburg, Matjaž Konvalinka
Pacific NW Combinatorics day, UWash, Seattle
24-25 Mar, Victoria   2018 Coast Combinatorics Conference University of Victoria, Victoria, BC
20 Mar Ryan Hayward, Alberta Recent results on Hex
13 Mar Seyyed Aliasghar Hosseini, Simon Fraser University Cops and Robbers on Graphs of Bounded Diameter
6 Mar Stephen Melczer, UPenn Eventual Positivity of Rational Function Coefficients
27 Feb Amanda Montejano Cantoral, Universidad Nacional Autónoma de México Forced chromatic patterns in 2-colorings of the complete graph
20 Feb (cancellation)  
13 Feb No seminar (Reading week)  
6 Feb Philippe Nadeau, Lyon/CNRS Combinatorics of the category of noncrossing partitions
30 Jan Samantha Dahlberg, UBC The e-positivity of claw-contractible-free graphs
23 Jan Karen Meagher, Regina Approaches to the Erdős-Ko-Rado Theorem
16 Jan Jessica McDonald, Auburn Edge-colouring planar graphs with precoloured edges

2017 Talks

Fall 2017

Dec 5 Karen Yeats
C&O Waterloo

A little progress on the completion invariance of the c2 invariant

 Nov 28 Koen van Greevenbroek
Math, SFU

 Contracted Difference Matrices

 Nov 21 Tony Huynh
Université Libre de Bruxelles

A tight Erdős-Pósa function for wheel minors

7 Nov Leonid Chindelevitch
Finding the rank median of three genomes
24 Oct Ross McConnell
Colorado State
Planar and Outerplanar Graphs
17 Oct Ron Aharoni
Israel Institute of Technology
Cooperative colorings
10 Oct Sheila Sundaram
Pierrepont School
Variations on the S_n-module Lie_n: results and conjecture
3 Oct Amanda Montejano
Universidad Nacional Autónoma de México
Zero-sum over Z
26 Sept Jehanne Dousse
Universität Zürich
Refinement of partition identities
19 Sept Moshe Rosenfeld
U of Washington
Starters what you know or don't care to know: old and new open problems
12 Sept Amelie Trotignon
 Simple Walks in the Three Quarter Plane

Summer 2017

29 Aug David Wood
Monash University
Monotone expanders and applications
08 Aug Aniket Mane
A tractable variant of the Single Cut or Join distance with duplicated genes
08 Aug
Abhinav Shantanam
Hadwiger Number of Complements of Kneser Graphs with \alpha = 2
01 Aug Dirk Nowotka
Kiel University
k-abelian pattern matching
25 July Cesar Hernandez Cruz
Universidad National Automate de Mexico
k-quasi-transitive digraphs of large diameter
25 July Samuel Simon
Linking Systems of Difference Sets
18 July Shuxing Li
Zhejiang University/SFU
Construction and nonexistence of strong external difference family
11 July Julian Sahasrabudhe
U of Cambridge
Exponential Patterns in Arithmetic Ramsey Theory
04 July Avi Kulkarni
Reading graphs into SAGE from an IPE diagram
04 July Sebastian Gonzalez Hermosillo de la Maza
Proper Orientations of Planar Bipartite Graphs
06 Jun
Arnaud Casteigts,
LaBRI, U de Bordeaux
Robustness in Highly Dynamic Networks
30 May Joao Meidanis,
U of Campinas, Brazil
Genome Matrices and the Median Problem
23 May
Stephen Melczer,
U of Waterloo
Effective Analytic Combinatorics in Several Variables
16 May Mark Kayll,
U of Montana
Derangements through the years: 1708--1996--2014

Spring 2017

18 April Julian Sahasrabudhe,
U of Cambridge
Exponential Patterns in Arithmetic Ramsey Theory
28 Mar Jonathan Jedwab,
Costas cubes
21 Mar
Pavol Hell, 
Obstruction Certificates for Geometrically Defined Graph (and Digraph) Classes
14 Mar David Rowe,
Universitat Mainz
*This Talk Will Begin At 2pm*
The Role of Configurations in Classical Algebraic Geometry
7 Mar Peter Wu,
On maximal size of 2-weakly compatible split system
28 Feb Sean Griffin,
U of Washington
Schur positivity and labeled binary trees
21 Feb Bojan Mohar,
The Crossing Number of the Cone of the Graph
7 Feb Fiachra Knox, 
Majority Colourings of Digraphs
31 Jan Luis Goddyn,
Parity Trackles on Surfaces and Perturbations of Bilinear Forms

2016 Talks

Fall 2016

Date Speaker, Affiliation Talk Title
20 Sep Tony Huynh,
U Libre de Bruxelles
The matroid secretary problem for minor-closed classes and random matroids
18 Oct Marni Mishna,
Universality classes for weighted lattice paths: where probability and ACSV meet
25 Oct Jørgen Bang-Jensen,
U of Southern Denmark
Connectivity properties of tournaments and semicomplete digraphs
1 Nov Seyyed Aliasghar Hosseini,
Cops and Robbers on Oriented Grids I
8 Nov Sebastian Gonzalez, SFU Cops and Robbers on Oriented Grids II
15 Nov Samantha Dahlberg, UBC Pattern Avoidance in Restricted Growth Functions
22 Nov Steffen Borgwardt, U of Colorado The Hirsch Conjecture is true for Network-Flow Polytopes
29 Nov Justin Chan, SFU Suitable Cores And Arrays
*Please Note Date/Location: 
         Talk on December 5th will be held in the IRMACS Theatre on MONDAY, Dec 5th

5 Dec Fan Chung Graham, U of California, San Diego
Sequences: random, structured or something in between?

Summer 2016

10 May Natalia García-Colín
U Nacional Autónoma de México
On the tolerated Tverberg number
17 May Jonathan Jedwab
Simon Fraser University
How many mutually unbiased bases can exist in complex space of dimension d?
24 May Dmitry Doryn
IBS Center for Geometry and Physics
c2 invariants of Feynman graphs
14 Jun César Hernández Cruz
U Autónoma de Zacatecas
A dichotomy for the kernel by H-walks problem in digraphs
21 Jun Flavia Bonomo
U Buenos Aires
Three-coloring and list three-coloring graphs without induced paths on seven vertices
28 Jun
Ross McConnell
Colorado State University
Algorithms on graphs arising from intersections of intervals
28 Jun Melissa Huggan
Dalhousie University
Conjoined games: go-cut and sno-go
5 Jul (extra)
Mathew Francis
Indian Statistical Institute, Chennai Centre
Uniquely restricted matchings in interval graphs
5 Jul Hendrik Süß
University of Manchester
Frobenius splitting of toric and T-varieties
12 Jul Bruce Reed
McGill University
How to determine if a random graph with a fixed degree sequence has a giant component
26 Jul Iain Crump
Simon Fraser University
The extended graph permanent as an affine variety
28 Jul
Mordecai Golin
Hong Kong UST
Optimal binary comparison search trees

Spring 2016

12 Jan Rodolphe Garbit
Université d'Angers
On the exit time from a cone for random walks with drift
19 Jan Suil O
Simon Fraser
Interlacing families and their application to digraphs
26 Jan
IRMACS Theatre
(12:00 reception)
Kilian Raschel
CNRS / U François Rabelais - Tours
Counting quadrant walks via Tutte's invariants and transformation theory of elliptic functions 
2 Feb Stefan Hannie
Simon Fraser
Immersion of 2-regular digraphs
9 Feb Reading break CANCELLED
16 Feb Pierre Tarrago
Saarlandes University
Categories of two-colored non-crossing partitions
1 Mar Cedric Chauve
Simon Fraser
Counting, generating and sampling tree alignments
8 Mar Julien Courtiel
Terminal chords in connected diagrams chords
15 Mar Claudia Linhares Sales
UF Ceará
B-continuity of lexicographic product of graphs
22 Mar Alejandro Morales
Hook Formulas for Skew Shapes
22 Mar
(2nd talk)
Barnaby Martin
Middlesex University London
The packing chromatic number of the infinite square lattice
29 Mar Fiachra Knox
Simon Fraser
Ramanujan gap for the norm of adjacency operators
5 Apr --- PIMS-SFU Colloquium: Anthony Várilly-Alvarado in IRMACS Theatre

2015 Talks

Fall 2015

22 Sept Ilya Shmulevich
Institute for Systems Biology
Probabilistic Boolean Networks as Models of Genetic Regulatory Networks
24 Sept
Harrison Chapman
University of Georgia
Asymptotic laws for knot diagrams
29 Sept Gary Greaves
Tohoku University
Equiangular lines in Euclidean spaces
6 Oct Karen Yeats
Simon Fraser
A few c_2 invariants of circulant graphs
13 Oct Abbas Mehrabian
Cops and a Fast Robber on Planar and Random Graphs
20 Oct Matt DeVos
Simon Fraser
Flows with large support
27 Oct Alejandro Erickson
Durham University
Graphs at the heart of the cloud
3 Nov Eric Fusy
CNRS / École Polytechnique
Baxter permutations and meanders
10 Nov Yota Otachi
Japan Advanced Institute of Science and Technology
Induced minor-free graphs: isomorphism and clique-width
17 Nov Theodore Kolokolnikov
Dalhousie University
Maximizing algebraic connectivity for certain families of graphs
24 Nov Shenwei Huang
Simon Fraser University
Colouring graphs without an induced path: A survey
1 Dec Luis Goddyn
Simon Fraser

Extending Hawiger’s Conjecture and Bicircular Matroids

8 Dec Campus closure CANCELLED
14 Dec
PIMS 8500
Chính Hoàng
Wilfred Laurier University
On the structure of (pan, even hole)-free graphs
14 Dec
PIMS 8500
Mark Giesbrecht
U Waterloo
Eigenvalues, invariant factors and random integer matrices (with a little bit of computing)

Summer 2015

12 May
Nicholas Beaton
U. Saskatchewan
Solvable self-avoiding walk and polygon models with large growth rates
19 May Matt DeVos
Simon Fraser
On nowhere-zero flows
26 May Luis Goddyn
Simon Fraser
Odd thrackles on surfaces
02 June CanaDAM 2015 CANCELLED
09 June Robert Samal 
Charles U.
Unique Vector Coloring and Cores
16 June Ron Graham conference CANCELLED
23 June Amanda Montejano
Cyclic orders and oriented 3-hypergraphs.
30 June Marni Mishna
Simon Fraser
Efficient uniform generation of reluctant walks
07 July Moshe Rosenfeld The wondering salmon problem and (unrelated) graph designs
14 July Christopher Duffy
Colourings and simple colourings of (j,k)-mixed graphs
23 July
Bruce Reed
McGill University
Connectivity preserving iterative compaction
28 July César Hernández-Cruz
Mixed cages
Acyclic disconnection and minimum feedback arc sets of graphs
04 August Jan Manuch

Spring 2015

Tuesday Jan 13
David Gajser, University of Ljubljana, Slovenia  Simple PTAS’s for families of graphs excluding a minor
Tuesday Jan 20
Martina Mockovciakova (University of West Bohemia, Pilsen, Czech Republic) Star Edge Coloring of Some Classes of Graphs
Tuesday Jan 27 (IRMACS,
12:30 reception)
Michael Singer (NCSU)
(PIMS Distinguished Visitor)
Galois theory of difference and differential equations.
Tuesday Feb 3
Manuel Kauers (RISC)
Walks in the Quarter Plane with Multiple Steps
Tuesday Feb 10
(Reading Week)
Tuesday Feb 17
Cedric Chauve, SFU Graph-theoretical algorithms to correct gene trees
Tuesday Feb 24
Edita Rollova (KMA) Homomorphisms and colourings of signed graphs
Tuesday Mar 3
Murilo da Silva Even-hole-free graphs
Tuesday Mar 10
Henry Liu, New University Lisbon, Portugal Connected subgraphs in edge-coloured graphs
Tuesday Mar 17
Ashok Rajaraman Vertex Ordering Problems for Hypergraphs: Connections to the Consecutive Ones Property
Tuesday Mar 24
Veronika Irvine (U Victoria) Lace patterns
Tuesday Mar 31
Guillaume Chapuy (Liafa/ Paris 7) Spanning trees of the graph of spanning trees.
Tuesday April 7 Karen Yeats (SFU) Rooted tree classes and the renormalization group equation
Tuesday April 14 Nathan Ilten (SFU) Counting lines on toric surfaces

2014 Talks

2013 Talks

2012 Talks

2011 Talks

2010 Talks

Seminars 2001-2010

Fall 2010
Tue Sept 14 / 2:30 / K9509 Zdenek Dvorak Choosability of planar graphs + Welcome party
Tue Sept 21 / 2:30 / K9509 Jessica McDonald, SFU Characterizing high chromatic index
Tue Sept 28 / 2:30 / K9509 Emmanuel Godard, CNRS/ U. Aix (Marseilles) Using isometric embeddings in distributed algorithms for the median problem in partial rectangular grids and their relatives
Tue Oct 5 / 2:30 / K9509 Mohamed Omar, UC Davis. Graph Automorphism and Permutation Groups via Polytopes
Tue October 12 / 2:30 / K9509 Karen Yeats, SFU The support of power series given by systems of equations
Tue October 19 / 2:30 / K9509 Cedric Chauve, SFU On matrices that do not have the Consecutive-Ones Property.
Tue October 26 / 2:30 / K9509 Andrew Crites, U. Washington Affine permutations and pattern avoidance
Tue Nov 2 / 2:30 / K9509 Petr Lisonek, SFU Non-linear functions
Tue Nov 9 / 2:30 / K9509 Flavio Guinez, UBC The reconstruction of a colored grid by its projections: a solution to the 2-atom problem in discrete tomography
Tue November 16 / 2:30 / K9509 Amites Sarkar, UWW Partitioning
geometric covers
Tue November 23 / 2:30 / K9509 Kurt Luoto, UBC Quasisymmetric and noncommutative Schur functions
Tue Nov 30 / 2:30 / K9509 Aki Avis, SFU 3-Phase Golay Triads
Tue Dec 7 / 2:30 / K9509 Pradeep Sarvepalli (UBC) Topological color codes over prime power alphabet
Satruday December 11 (Western Washington University) Combinatorial potlatch Richard Guy, University of Calgary
Christine Kelley, University of Nebraska, Lincoln
Kai-Uwe Schmidt, Simon Fraser University
Tue Dec 14 / 2:30 / K9509 Bruce Shepherd Minimum Cost Networks Supporting All Matchings
Summer 2010
Tue 08 Jun / 2:30 / K9509 John Stardom, Statistics Canada Sample Stratification and Allocation: an Application to Statistics Canada's Unified Enterprise Survey
Tue 22 Jun / 2:30 / K9509 Christian Stump, CRM/ LaCIM UQAM Non-crossing and non-nesting partitions and the cyclic sieving phenomenon
Tue 07 July / 2:30 / K9509 Karel Casteels, SFU Combinatorial aspects of the prime spectrum of quantum matrices
Tue 13 July / 2:30 / K9509 Guillaume Chapuy, SFU Covered Maps on Orientable Surfaces
Tue 10 August / 2:30 / K9509 Kai-Uwe Schmidt, SFU Appended m-sequences with merit factor greater than 3.34
Spring 2010
Tue 09 Feb / 3:30 / TASC2 8500 Kevin Milans, U. Illinois UC Degree Ramsey Numbers of Graphs
Tue 02 Mar / 3:30 / TASC2 8500 Ararat Harutyunyan, SFU Independent dominating sets in graphs of girth five
Thu 04 Mar / 1:00 / K 9509 Adolfo Rodriguez, LaCIM UQAM Bugs, colonies, and q-Boson normal ordering
Tue 23 Mar / 3:30 / TASC2 8500 Roland Wittler, Bielefeld and SFU. Phylogeny-based Analysis of Gene Clusters
Thu 25 Mar / 1:00 / K 9509 Justin Chan, University of Victoria The Lamken-Wilson Theorem and Its Applications
Mon 12 Apr / 2:30 / IRMACS Theatre, ASB 10900, SFU Peter Horak, U. Washington, Tacoma Tiling n-space by cubes
Tue 13 Apr / 3:30 / TASC2 8500 Alejandro Erickson, University of Victoria Negative correlation properties for graphs
Tue 20 Apr / 3:30 / TASC2 8500 Robert Samal, Charles University, Prague Star Chromatic Index
Fall 2009
Tue 22 Sep / 1:30 / K9509 Bojan Monar, SFU How useful can the spectral radius of a graph be?
Tue 29 Sep / 1:30 / K9509 Ladislaw Stacho Cyclic colorings of plane graphs with independent faces
Tue 06 Oct / 1:30 / K9509 Guillaume Chapuy Maps on surfaces : asymptotic enumeration and metric properties.
Tue 13 Oct / 1:30 / K9509 Andrea Spencer, SFU Title: Efficient Edge List Colouring of Cubic Planar Graphs
Tue 27 Oct / 1:30 / K9509 Mahdad Khatirinejad-Fard, Helsinki U. of Tech. Title: Edge-weighting vertex colouring of (di)graphs
Sat 21 Nov / 10:00 / Labatt Room 2009 Combinatorial Potlach, SFU Harbour Centre Speakers: TBA
Summer 2009
Tue 05 May / 2:00 / TASC2 8500 Daniel Kral, Charles U., Prague Removal Lemma for systems of linear equations
Tue 25 Aug / 3:30 / K9509 Gena Hahn, U. de Montreal Cops and Robbers on Infinite Graphs
Tue 01 Sep / 3:30 / K9509 Robert Samal, Charles U., Prague Cubical chromatic number, spherical chromatic number, and Lovasz theta function
Spring 2009
Tue 10 Feb / 3:30 / K9509 Robert Bailey, Carleton University Packing spanning trees in graphs and bases in matroids
Sat-Sun 21-22 Feb, Univ. of Victoria 11th Coast Combinatorics Conference  
Tue 24 Feb / 3:30 / K9509 Markus Grassl, Centre for Quantum Technologies (NUS), Singapore Searching for good error-correcting codes
Tue 31 Mar / 3:30 / K9509 Hernando Bermudez, University of Montana Sheduling Tournaments with Home and Away Constraints
Tue 24 Mar / 3:30 / K9509 Natasa Przulj, UC Irvine From Network Topology to Biological Function and Disease
Tue 14 Apr / 3:30 / K9509 Cedric Chauve Enumerative results for graph decompostion trees
Tue 21 Apr / 3:30 / K9509 Eric Fusy Schnyder woods generalized to higher genus surfaces
Tue 28 Apr / 3:30 / K9509 Bruce Richter, University of Waterloo Do we really know what characterizes planarity?
Fall 2008
Tue 23 Sep / 3:30 / K9509 Juanjo Ru\'e, Politechnical U. of Catalonia On a question of S\'arkozy and S\'os on bilinear forms
Thu 02 Oct / 1:30 / K9509 Mireille Bousquet-Melou, CNRS, Bordeaux Enumeration of colored planar maps
Tue 14 Oct / 3:30 / K9509 Eli Berger, Univeristy of Haifa Using classical topology in combinatorial problems.
Tue 28 Oct / 2:30 / ASB 10900 David Brydges, CRC Chair, UBC Combinatorics with Gaussian Integreals
Tue 04 Nov / 3:30 / K9509 Ken-ichi Kawarabayashi, Nat. Inst. of Informatics, Japan From the Plane to Higher Surfaces
Tue 18 Nov / 3:30 / K9509 Aida Ouangraoua, SFU Algorithmic tools to compare tree-structured biological objects
Sat 22 Nov / 10:00 / U.P.S. 2008 Combinatorial Potlach, U. Puget Sound, Tacoma Speakers: E. Fusy + C. Dunn + I. Dumitriu
Tue 02 Dec / 3:30 / K9509 Brian Alspach, U. Newcastle Hamilton paths in vertex-transative graphs
Summer 2008
Tue 06 May / 3:30 / K9509 Bojan Mohar, SFU On the sum of k largest eigenvalues of graphs and symmetric matrices
Tue 20 May / 3:30 / K9509 Simon Spacapan, SFU The Acyclic, the Star, and the Degenerate Chromatic Numbers
Tue 22 Jul / 3:30 / K9509 Winfried Hochstaettler, U. of Hagen, Germany Flows in Oriented Matroids and a Chromatic Number
Tue 19 Aug / 2:30 / TASK 9204 David Coudert, CNRS U. Nice Sophia Survivability and Routing in Oriented Networks
Spring 2008
Tue 15 Jan / 3:30 / K9509 Maia Fraser, U. Colima, Mx Local routing on higher surfaces
Tue 25 Feb / 3:30 / K9509 Gabor Kun, Etvos University, Hungary Cops and robbers in random graphs
Tue 04 Mar / 3:30 / K9509 Luis Goddyn, Simon Fraer University How bad can a Euclidean Traveling Salesman Problem be?
Tue 11 March / 3:30 / TASC2 8500 Penny Haxell, University of Waterloo More on Sperner's Lemma
Tue 25 March / 3:30 / K9509 Agelos Georgakopoulos, University of Hamburg Infinite cycles in graphs
Tue 25 March / 3:30 / K9509 Marni Mishna, Simon Fraser University Decomposition and Enumeration of Planar Graphs, Part I: Combinatorial Warm Up
Tue 01 April / 3:30 / K9509 Eric Fusy, Simon Fraser University Decomposition and Enumeration of Planar Graphs, Part II
Tue 08 April / 3:00 / K 9509 Laura Chavez, Simon Fraser University Flow and chromatic numbers for matroids (reception to follow)
Tue 15 April / 3:30 / K 9509 Derek Bingham, Simon Fraser University Defining contrast subspaces and the randomization structure of factorial designs
Tue 29 April / 3:30 / K 9509 Sean McGuinness, Thompson Rivers University Perfect Path Double Covers, Matroids, A Theorem of Fan, ... And A Problem of Goddyn.
Fall 2007
Tue 25 Sep / 10:30 / ASB10900 Luis Goddyn, SFU (Coast to Coast) Spectra of (3,6)-Fullerenes
Tue 25 Sep / 2:30 / TASC2 8500 Mark Siggers, SFU Integer packings of hypergraphs through fractional packings
Sat 29 Sep / 11:00 / U. Victoria 2007 Combinatorial Potlach Speakers: Perkel + Moon + Quas
Tue 02 Oct / 2:30 / TASC2 8500 Robert Samal, SFU Trading Handles for Crossings
Tue 09 Oct / 2:30 / TASC2 8500 Blair D Sullivan, Princeton Feedback Arc Sets in Circular Interval Digraphs
Tue 23 Oct / 2:30 / TASC2 8500 Gabor Kun, SFU An asymptotic version of the Bollobas-Catlin-Eldridge conjecture
Tue 30 Oct / 2:30 / TASC2 8500 Matthias Koeppe, U. Magdeburg, de Topic: Ehrhart polynomials of matroid polytopes
Tue 06 Nov / 2:30 / TASC2 8500 Eric Fusy, SFU Transversal structures on triangulations: combinatorial study and algorithmic applications
Tue 13 Nov / 2:30 / TASC2 8500 Vladmir Korzhik, Nat. U. Chernivtsi, Ukraine Some open problems on the set of triangular embeddings of a complete graph
Tue 27 Nov / 2:30 / TASC2 8500 Frederic Giroire, Intel Research Probabilistic algorithms to compute the cardinality of very large datasets
Summer 2007
Tue 15 May / 3:30 / ASB10908 Ambat Vijayakumar Graph operators and co-graphs: some recent trends
Fri 18 May / 1:30 / ASB10900 Andre Raspaud Injective Colourings of Graphs
Tue 22 May / 3:30 / ASB10908 Jonathan Jedwab, SFU Golay complementary sequences: a multi-dimensional approach
Thu 24 May / 11:30 / ASB10900 Janos Pach Decomposition of multiple coverings
Fri 25 May / 2:30 / ASB10900 Herbert Wilf Mathematics: An experimental science
Fri 31 Aug / 2:30 / 1430 SFU Harbour Centre Paul Seymour Structure Theorems in Graph Theory
Spring 2007
Tue 30 Jan / 3:30 / ASB10908 Azhvan Sheikh-Ahmady, SFU Eigenvalues of Cayley graphs and group characters.
Tue 6 Feb / 3:30 / ASB10908 Cedric Chauvre, SFU Inferring ancestral genomes with common intervals
Tue 20 Feb / 3:30 / ASB10908 Neil Robertson, Ohio State U. CANCELLED
SatSun 24-25 Feb /9:30 / U. Victoria Eighth Coast Combinatorics Conference Speakers: Several
Tue 27 Feb / 3:30 / ASB10908 Gena Hahn, Universite de Montreal CANCELLED
Tue 06 Mar / 3:30 / ASB10908 Francois Bergeron, UQAM A combinatorial classification of polynomials
Tue 13 Mar / 3:30 / ASB10908 Mike Zabrocki, York U. A Zoo of Hopf Algebras
Tue 20 Mar / 3:30 / ASB10908 Robert Samal, SFU On XY mappings
Tue 27 Mar / 3:30 / ASB10908 Jonathan Jedwab, SFU On XY mappings
Fall 2006
Tue 26 Sep / 3:30 / ASB10908 Tamon Stephen, SFU Colourful Simplicial Depth
Wed 27 Sep / 3:30 / ASB9705 Eyal Ackerman, SFU Maximum size of a $k$-quasi-planar graphs
Tue 10 Oct / 3:30 / (UBC) WMAX110 Joachim Rosenthal, U. Zurich Three challenges of Claude Shannon
Tue 17 Oct / 3:30 / ASB10908 Tomas Kaiser, U. West Bohemia Non-intersecting perfect matchings in cubic graphs
Tue 31 Oct / 2:30 / ASB10900 Dragos Cvetkovic, U. of Belgrade Signless Laplacians of finite graphs
Sat 11 Nov / 10:00 / Portland State U. 2006 Combinatorial Potlach Speakers: Brualdi + Gordon + DeVos
Tue 21 Nov / 3:30 / ASB10900 Kevin Purbhoo, UBC Puzzles, Tableaux, and Mosaics
Tue 05 Dec / 3:30 / (UBC) WMAX110 John Gimbel, University of Alaska Remarks on split graphs and related notions
Tue 12 Dec / 2:30 / ASB10900 Moshe Rosenfeld, University of Washington, Tacoma Spanning Graph Designs, an extension of the "Graph disease"
Tue 12 Dec / 3:30 / ASB10900 John Irving, St. Mary's University Counting Transitive Factorizations in the Symmetric Group
Summer 2006
Tue 7 May / 3:30 / ASB10908 Winfried Hochstaettler, Fern Univ at Hagen Online matching on a line
Thu 22 Jun / 9:30 / ASB10900 SFU Discrete Math Day Seven talks by distinguished visitors
Thu 29 Jun / 2:30 / AQ 3149 Winfried Hochstaettler, Fern Univ at Hagen On the game chromatic index of trees
Tue 4 Jul / 3:30 / K9509 Brian Lucena, American Univ. in Cairo Minimal forbidden minors for treewidth
Tue 8 Aug / 3:30 / ASB10900 Jacob Fox Ramsey-type results for intersection graphs:w
Spring 2006
Tue 24 Jan / 3:30 / ASB10900 Maria Chudnovski, Princeton U. The structure of bull-free graphs
Tue 14 Feb / 3:30 / ASB10900 Luis Goddyn, SFU Silver Cubes
Tue 28 Feb / 3:30 / (UBC) WMAX216 Shakhar Smorodinsky, Courant Inst. On K-sets in dimensions 2, 3 and 4.
Tue 14 Mar / 3:30 / ASB10900 Arie Bialostocki, University of Idaho Some Problems in View of Recent Developments of the Erdos Ginzburg Ziv theorem
Tue 21 Mar / 3:30 / ASB10900 Susan Barwick, University of Adelaide The geometry of linear perfect hash families
Tue 28 Mar / 3:30 / (UBC) WMAX216 Kee Yuen Lam, UBC The combinatorics of sums of squares as studied via topology
Tue 4 Apr / 3:30 / ASB10908 Aidan Roy, University of Waterloo Equiangular lines, mutually unbiased bases, and difference sets
Fall 2005
Tue 13 Sep / 3:30 / (UBC) WMAX216 Gabor Tardos, SFU Toward and Extremal Theory of Ordered Graphs
Tue 20 Sep / 3:30 / ASB10908 Brian Alspach, University of Regina Time constrained searching and sweeping
Tue 27 Sep / 3:30 / ASB10908 Richard Anstee, UBC Forbidden Configurations: An update
Tue 04 Oct / 3:30 / EAA1100 Matt DeVos, SFU Pentagon Colouring
Tue 11 Oct / 3:30 / ASB 10900 Bojan Mohar, SFU Quadrangulations, Eulerian triangulations, and 5-critical graphs
Tue 25 Oct / 3:30 / (UBC) WMAX216 David Kirkpatrick, UBC Minimizing precision/input in the evaluation of geometric primitives
Tue 08 Nov / 3:30 / (UBC) WMAX216 Luis Goddyn, SFU An Optimization Problem Arising from Video-on-Demand Broadcasting
Wed 09 Nov / 3:30 / ASB10908 Santosh Kabadi, U New Brunswick Integer Exact Network Synthesis Problem
Tue 15 Nov / 3:30 / ASB10908 Jonathan Jedwab, SFU Proof of the Barker Array Conjecture
Sat 19 Nov / 10:30 / Seattle U. 2005 Combinatorial Potlach Speakers: Mohar + Quinn + Caughman
Summer 2005
Tue 03 May / 3:30 / EAA1100 Cedric Chauve, Universite du Quebec a Montreal Conservation of combinatorial structure in genome rearrangement scenarios
Tue 17 May / 3:30 / EAA1100 Rados Radoicic, Rutgers University Intersection patterns of geometric objects
Tue 31 May / 3:30 / EAA1100 Danny Dyer, University of Regina Digraphs with small sweep number
Tue 21 Jun / 3:30 / EAA1100 Anna Galluccio, IASI-CNR, Roma, Italy Regular Join Graphs
Tue 28 Jun / 3:30 / ASB 10900 CANCELLED: Mordecai Golin, Hong Kong U. of Science The Knuth-Yao Quadrangle-Inequality & Total-Monotonicity
Wed 06 Jul / 3:30 / ASB 10900 Ebad Mahmoodian, Sharif University Problems and Motivations
Tue 19 Jul / 3:30 / EAA1100 Ron Aharoni, Technion Institute, Israel Topological Methods in Matching Theory
Spring 2005
Tue 18 Jan / 3:30 / EAA1100 Colin Percival, University of Oxford Matching with mismatches
Thu 10 Feb / 3:30 / EAA1100 Peter Horak, University of Washington Completing Latin squares
Tue 15 Feb / 3:30 / EAA1100 Binay Bhattacharya, Simon Fraser University Collection depots problem on networks
Tue 22 Feb / 3:30 / EAA1100 Evangelos Kranakis, Carleton University The Mobile Agent Rendezvous Problem
Mon 28 Feb / 4:00 / K9509 Chris Mitchell, Royal Holloway Cryptanalysis of methods for combining confidentiality and integrity
Tue 1 Mar / 3:30 / EAA1100 Nati Linial, U. Washington & Hebrew University Finite Metric Spaces - A quick overview
Tue 15 Mar / 3:30 / EAA1100 Frank Fiedler, Simon Fraser University The Search for More Golay Sequences
Tue 22 Mar / 3:30 / EAA1100 Petr Lisonek, Simon Fraser University Enumeration of Codes of Fixed Cardinality up to Isomorphism
Tue 29 Mar / 4:30 / AQ 3182 Laszlo Lovasz, Microsoft Research and Eotvos Lorand University Graph homomorphisms, statistical physics, and limits of graph sequences
Tue 05 Apr / 3:30 / EAA1100 Boaz Benmoshe, Simon Fraser University Guarding 1.5D terrains
Fall 2004
Tue 21 Sep / 2:30 / K9509 Abraham P. Punnen, University of New Brunswick The number of distinct tour values for the traveling salesman problem: one, two, three, all
Tue 28 Sep / 3:30 / EAA1100 Arash Rafiey, University of London Characterization of edge-colored complete graphs with properly colored Hamilton paths
Tue 5 Oct / 3:30 / EAA1100 Frank Fiedler, Simon Fraser On the degree of Mathon maximal arcs
Tue 12 Oct / 3:30 / EAA1100 Jonathan Jedwab, Simon Fraser A survey of the merit factor problem for binary sequences
Tue 19 Oct / 3:30 / EAA1100 Ladislav Stacho, Simon Fraser Asymptotics of random RNA
Tue 26 Oct / 3:30 / EAA1100 Jeffrey Farr, Simon Fraser Large caps with free pairs in PG(N,q)
Tue 2 Nov / 3:30 / EAA1100 Mohammad Ghebleh, Simon Fraser Circular chromatic number of even-faced torus graphs
Tue 9 Nov / 3:30 / EAA1100 Petr Lisonek, Simon Fraser Variable rate linear codes with an application to steganography
Tue 16 Nov / 3:30 / EAA1100 Luis Goddyn, Simon Fraser Two results for the Lonely Runner
Sat 20 Nov / 10:30 / Harbour Centre   Combinatorial Potlatch 2004
Tue 23 Nov / 3:30 / EAA1100 Pavol Hell, Simon Fraser Matrix partitions of perfect graphs
Tue 30 Nov / 3:45 / EAA1100 Xuding Zhu, National Sun Yat-sen University Circular coloring of Kneser graphs, Schrijver graphs and cones over graphs
Tue 7 Dec / 3:30 / EAA1100 Victor Dalmau, Universitat Pompeu Fabra Constraint Satisfaction Problems and Expressiveness
Summer 2004
Tue 18 May / 3:30 / EAA1100 Daniel Kral, Charles University Circular edge-colorings of graphs with large girth
Fri 28 May / 11:30 / EAA1100 Peter Pleasants, University of Queensland Almost disjoint families of 3-term arithmetic progressions
Fri 28 May / 2:30 / K9509 Nantel Bergeron, York University Combinatorial Hopf algebras
Mon 31 May / 2:30 / K9509 Bojan Mohar, University of Ljubljana Graph minors and graphs on surfaces
Tue 29 Jun / 2:30 / K9509 Marni Mishna, LaBRI, University of Bordeaux On the utility of effective D-finite symmetric functions in combinatorics
Tue 13 Jul / 3:30 / EAA1100 Bruce Reed, McGill University Vertex Colouring Edge Weightings
Tue 20 Jul / 2:30 / K9509 Nadya Shirokova, Inst. Hautes Etudes Sci. Space approach to invariants for families
Tue 27 Jul / 10:00 / Halpern Centre, Room 126 Roman Nedela, Slovak Academy of Sciences Regular maps - combinatorial objects relating different fields of mathematics
Tue 10 Aug / 3:30 / EAA1100 Moshe Rosenfeld, University of Washington Prisms over graphs
Tue 17 Aug / 3:30 / EAA1100 Tomas Kaiser, University of West Bohemia Eulerian colorings of graphs
Spring 2004
Tue 20 Jan / 3:30 / EAA1100 Jim Davis, Math & CS, U of Richmond Polynomial arithmetic behind the IEEE 802.12 standard for 100Mbit/s data transmission
Tue 27 Jan / 3:30 / EAA1100 Jeffrey Farr, Mathematics, SFU A new polynomial construction for some linear codes
Tue 03 Feb / 3:30 / EAA1100 Petr Lisonek, Mathematics, SFU Binary caps with many free pairs of points
Tue 10 Feb / 3:30 / EAA1100 Jan Manuch, Computing, SFU Inverse protein folding in 2D HP model
Tue 17 Feb / 3:30 / EAA1100 SEMINAR CANCELLED Reading break
Tue 24 Feb / 3:30 / EAA1100 Ladislav Stacho, Mathematics, SFU Traversal of quasi-planar subdivisions without using mark bits
Tue 01 Mar / 3:30 / EAA1100 Chris Mitchell, U of London, UK Universal cycles of permutations
Tue 02 Mar / 3:30 / EAA1100 Mahdad Khatirinejad Fard , Mathematics, SFU IC-Colorings and IC-indices of graphs
Thu 11 Mar / 11:30 / K9509 (!) Juergen Bierbrauer, Michigan Technological University Cyclic codes and their applications
Tue 16 Mar / 3:30 / EAA1100 Veselin Jungic, Mathematics, SFU Rainbow Ramsey Theory
Tue 23 Mar / 3:30 / EAA1100 Van Vu, Mathematics, UCSD Erdos-Folkman conjecture
Tue 30 Mar / 3:30 / EAA1100 Luis Goddyn, Mathematics, SFU From graceful labelings to Heawood embeddings
Tue 06 Apr / 3:30 / EAA1100 Jozsef Solymosi, Mathematics, UBC Applications of hypergraph regularity
Fall 2003
Tue 30 Sep / 3:30 / EAA1100 Jan Manuch, Math & CS, SFU On f-wise Arc Forwarding Index and Wavelength Allocations in Faulty All-optical Networks
Tue 07 Oct / 3:30 / EAA1100 Luis Goddyn, Mathematics, SFU Packing Group-non-vanishing A-paths
Tue 14 Oct / 3:30 / EAA1100 Ladislav Stacho, Mathematics, SFU Closure for the Property of Having a Hamiltonian Prism
Tue 21 Oct / 3:30 / EAA1100 Petr Lisonek, Mathematics, SFU A New Application of the Linear Programming Method in Coding Theory
Tue 04 Nov / 3:30 / EAA1100 Russel Martin, Computing, U of Warwick Rapidly Mixing Markov Chains for Sampling Contingency Tables with a Constant Number of Rows
08-10 Nov / / UVic   Combinatorial Potlatch and 5th Coast Combinatorics Conference 
Thu 13 Nov / 3:30 / EAA1100 Zdenek Ryjacek, Mathematics, U of West Bohemia Closure Concepts, Stable Properties and Forbidden Subgraphs for Hamiltonicity
Tue 18 Nov / 3:30 / AQ 3149 Helaman and Claire Ferguson Mathematics in Stone and Bronze (The Alan Mekler Lecture)
Tue 25 Nov / 3:30 / EAA1100 Alireza Hadj Khodabakhshi, Computing, SFU A Fast Algorithm for Finding a Global Alignment Between Two Genomes
Spring 2003
Tue 07 Jan / 3:30 / EAA1100 Reza Naserasr, Mathematics, SFU Homomorphisms of Planar Graphs
Tue 14 Jan / 3:30 / EAA1100 Pavol Hell, Mathematics/Comp. Sci., SFU Interval Bigraphs and Circular Arc Graphs
Tue 21 Jan / 3:30 / EAA1100 Romeo Rizzi, University of Trento (Italy) Permutation Routing on POPS Networks
Tue 28 Jan / 3:30 / K9509 (!) Nantel Bergeron, Mathematics and Statistics, York University Quasi-symmetric Polynomials and Temperley-Lieb Invariants and Covariants
Tue 11 Feb / 3:30 / EAA1100 Tom Friedetzky, Comp. Sci., SFU A Proportionate Fair Scheduling Rule with Good Worst-case Performance
Tue 18 Feb / 3:30 / EAA1100 Jan Manuch, SFU Equations on Words and Defect Theorems
Tue 25 Feb / 10:30 (!) / K9509 Wendy Myrvold, University of Victoria Hunting for Torus Obstructions
Tue 25 Feb / 3:30 / EAA1100 Jaroslav Nesetril, Charles University, Prague Ramsey Classes and Homogeneous Graphs
Tue 04 Mar / 3:30 / EAA1100 Veselin Jungic, Mathematics, SFU Colorings of Plane Graphs with No Rainbow Faces
Tue 11 Mar / 3:30 / EAA1100 Jessie Zhu, SFU Phylogenetics Incorporating Stratophenetics
Tue 18 Mar / 3:30 / EAA1100 Riste Skrekovski, PIMS/SFU Coloring 1001 Maps on Surfaces
Tue 25 Mar / 3:30 / EAA1100 Stephanie van Willigenburg, Mathematics, U. British Columbia Acyclic Orientations and Excedence Permutations
Tue 15 Apr / 10:30 (!) / ASB 9896 (!) Yuri Gurevich, Microsoft Research What is Polynomial Time Anyway?
Tue 15 Apr / 3:30 / EAA1100 Joel Friedman, Mathematics, U. British Columbia A Proof of Alon's Second Eigenvalue Conjecture
Tue 29 Apr / 3:30 / EAA1100 Michael Molloy, Microsoft Research and University of Toronto Random Constraint Satisfaction Problems, aka Homomorphisms of Random Hypergraphs
Fall 2002
Tue 10 Sep / 2:00 / EAA1100 Juan Jose Montellano-Ballesteros, UNAM Mexico Polychromatic Cliques
Tue 17 Sep / 2:00 / EAA1100 Ladislav Stacho, Mathematics, SFU Edge-disjoint Spanners in Multi-dimensional Torus
Tue 24 Sep / 2:00 / EAA1100 Jan Manuch, SFU On the Descriptional and Computational Complexities of Infinite Words
Tue 01 Oct / 2:00 / EAA1100 Tom Brown, Mathematics, SFU On the Canonical Version of a Simple Theorem in Ramsey Theory
Tue 08 Oct / 2:00 / EAA1100 Petr Lisonek, Mathematics, SFU A Family of Complete Caps in PG(n,2)
Tue 15 Oct / 2:00 / EAA1100 Riste Skrekovski, PIMS/SFU Cyclic, Diagonal, and Facial Colorings
Tue 22 Oct / 2:00 / EAA1100 Veselin Jungic, Mathematics, SFU Radoicic's Conjecture and Tight Graphs
Tue 29 Oct / 2:00 / EAA1100 Bruce Reed, McGill University Tree Width and Excluded Minors
Tue 05 Nov / 2:00 / EAA1100 Richard Anstee, Mathematics, U. British Columbia Forbidden Configurations
Sat 09 Nov / 11-6 / UVic A. Proskurowski, B. Grunbaum, J. Siran Combinatorial Potlatch at UVic
Tue 12 Nov / 2:00 / EAA1100 Qianping Gu, Comp. Sci., SFU A 1.8-Approximation Algorithm for Embedding Hypergraphs in a Cycle
Tue 19 Nov / 2:00 / EAA1100 Daniel Kral, Charles University Channel Assignment Problem
Thu (!) 21 Nov / 2:00 / EAA1100 Vadim V. Lozin, Rutgers Boundary Classes of Graphs for NP-hard Problems
Tue 26 Nov / 2:00 / EAA1100 Ron Ferguson, PIMS/SFU Polyphase Sequences with Low Autocorrelation
Tue 03 Dec / 2:00 / EAA1100 Cynthia Loten , Mathematics, SFU Retractions and a Generalization of Chordal Graphs
Summer 2002    
Tue 14 May / 3:30 / EAA1100 Rados Rodoicic, MIT Rainbow Arithmetic Progressions
Tue 28 May / 3:30 / EAA1100 Sean McGuinness, U. Umea and Montana Circuits intersecting cocircuits in graphs and matroids.
Tue 11 Jun / 3:30 / EAA1100 Claude Tardif, U. Regina The projectivity of the graphs $G_d^k$
Tue 18 Jun / 3:30 / K9509 Joergen Bang-Jensen, U. Southern Denmark Steiner type problems in tournament-like digraphs
Tue 25 Jun / 3:30 / K 9500 (!) Winfried Hochstaettler, Brandenburg U. of Tech. Max-flow min-cut duality for a paint shop problem
Tue 02 Jul / 3:30 / EAA1100 Luis Goddyn, Mathematics, SFU Flows and Tensions on maps of high edge width.
Tue 09 Jul / 3:30 / EAA1100 Peter Higgins, Mathematics, Sur une Th\'eor\`eme de Sierpi\'nsk (In English!)
Tue 16 Jul / 3:30 / EAA1100 Khee-Meng Koh, Nat. U. of Singapore On the Chromaticity of graphs
Tue 23 Jul / 3:30 / EAA1100 UBC PiMS Event - Lovasz See their program for titles and abstracts.
Tue 30 Jul / 3:30 / EAA1100 Marnie Mishna Enumeration via D-finite Symmetric Functions
Tue 6 Aug / 3:30 / EAA1100 Luis Goddyn Chromatic numbers of matroids
Tue 6 Aug / 3:30 / EAA1100 Bill McCuaig Edmonds' arc-disjoint arborescences theorem
Spring 2002
Tue 05 Feb / 3:30 / EAA1100 Reza Naserasr, Math, SFU Homomorphisms from sparse graphs with large girth.
Tue 12 Feb / 3:30 / EAA1100 Qianping Gu, CS, SFU Permutation routing on WDM optical hypercubes I.
Tue 19 Feb / 3:30 / EAA1100 Qianping Gu, CS, SFU Permutation routing on WDM optical hypercubes II.
Tue 05 Mar / 3:30 / EAA1100 Luis Goddyn, Math, SFU Graph coloring and Matroids.
Tue 05 Mar / 3:30 / EAA1100 Tom Friedetzky, CS, SFU The Natural Work-Stealing Algorithm is Stable
Tue 19 Mar / 3:30 / EAA1100 Petr Lisonek, Math, SFU Caps and Binary Linear Codes
Tue 26 Mar / 3:30 / EAA1100 Petra Berenbrink, CS, SFU Simple routing strategies for Adversarial networks.
Tue 02 Apr / 3:30 / EAA1100 Pavol Hell, CS/Math, SFU Complexity of generalized list-colourings.
Tue 09 Apr / 3:30 / EAA1100 Laco Stacho, Math, SFU Edge-disjoint spanners in the Cartesian product of graphs
Fall 2001
Tue 18 Sep / 3:30 / EAA1100 Luis Goddyn, Math, SFU Binary Gray Codes with long bit runs.
Tue 25 Sep / 3:30 / EAA1100 Louis Ibarra, CS, SFU The clique-separator graph for chordal graphs and its subclasses.
Tue 02 Oct / 3:30 / EAA1100 Ladislav Stacho, Math, SFU New upper-bound for chromatic number.
Tue 09 Oct / 3:30 / EAA1100 Amitava Bhattacharya, TIFR A short proof of a EKR type theorem.
Tue 16 Oct / 3:30 / EAA1100 Juan Montellano, UNAM Anti-Ramsey Problems.
Tue 23 Oct / 3:30 / EAA1100 Ladislav Stacho, Math, SFU Spannin trees with bounded number of branch vertices.
Tue 30 Oct / 3:30 / EAA1100 Bill McCuaig, Math, SFU The Hat Game.
Tue 06 Nov / 3:30 / EAA1100 Mohammad Ghebleh, Math, SFU Uniuqely list colorable graphs.
Tue 13 Nov / 3:30 / EAA1100 Petr Lisonek, Math, SFU Geometric Representations of Graphs.
Tue 20 Nov / 3:30 / EAA1100 Luis Goddyn, Math, SFU Using the Nullstellensatz for edge list colouring.
Tue 27 Nov / 3:30 / EAA1100 Reza Naserasr, Math, SFU On the covering number of graphs.
Tue 04 Dec / 3:30 / EAA1100 Roded Sharan, Technion, Haifa Incomplete Directed Perfect Phylogeny.
Tue 11 Dec / 3:30 / EAA1100 Frederic Havet, CNRS, France Design of fault tolerant on-board networks with priorities
Tue 18 Dec / 3:30 / EAA1100 Mirka Miller, Newcastle, Australia Eccentric Digraphs
Summer 2001
Thu 10 May / 3:30 / EAA1100 John Mighton, Fields Inst. A New Reduction of Graph Theory and Binary Matroids
Tue 15 May / 3:30 / EAA1100 Sergei Bespamyatnikh, CS, U. British Columbia Graph of triangulations of convex polytopes in R^3
Tue 26 Jun / 3:30 / K9509 Matt DeVos, Princeton U. On Packing T-Joins
Tue 10 Jul / 3:30 / EAA1100 Moishe Rosenfeld, U. of Washington Hamiltonian Decomposition of Prisms over cubic graphs
Tue 17 Jul / 3:30 / K9509 Claude Tardif, U. of Regina Fractional aspects of Hedetniemi's conjecture
Spring 2001
Tue 30 Jan / 3:30 / K9509 Reza Naserasr, Math, SFU On $\Delta$-critical graphs
Wed 31 Jan / 2:30 / K9509 Brett Stevens, Math, SFU Packing and covering designs
Tue 06 Feb / 3:30 / K9509 Luis Goddyn, Math, SFU Range-restricted flows in regular matroids.
Tue 13 Feb / 3:30 / EAA1100 Jarik Nesetril, Charles University, Prague On a homomorphism duality for oriented trees.
Tue 20 Feb / 2:30 / EAA1100 Valentine Kabanets, Inst. for Advanced Study In search of an easy witness: Exponential time vs probabilistic polytime.
Tue 20 Feb / 3:40 / EAA1100 Wayne Broughton, Okanagan University Coll. Quasi-3 Designs and Hadamard Matrices.
Wed 28 Feb / 3:30 / K9509 Pavol Hell, SFU List homomorphisms and partitions
Tue 6 Mar / 3:30 / EAA1100 Steph Durocher, U. British Columbia The tangled tale of the rectilinear crossing number of K_n
Tue 13 Mar / 3:30 / EAA1100 Richard Anstee, U. British Columbia Small Forbidden Configurations
Tue 20 Mar / 3:30 / EAA1100 Brett Stevens, Math, SFU Packing Arrays II: Beyond Codes, the Triumphant Return of Designs!
Tue 27 Mar / 2:30 / EAA1100 Lou Ibarra, U. Victoria Dynamic algorithms for chordal and interval graphs.
Tue 27 Mar / 3:30 / EAA1100 Jonathan Jedwab, Hewlett-Packard Labs, Bristol Combinatorial Design Theory in an Industrial Research Lab
Wed 28 Mar / 2:30 / K9509 William Evans, U. British Columbia Recovering lines with fixed linear probes
Wed 28 Mar / 3:30 / K9509 Petr Lisonek, Math, SFU Classification of Binary Linear Codes with Small Codimension
Tue 3 Apr / 3:30 / EAA1100 Mateja Sajna, Capilano Coll. Decomposition of complete graphs into cycles of a fixed length
Wed 4 Apr / 3:30 / K9509 Veselin Jungic, Math, SFU Diophantine Ramsey Theory and Recurrence in Dynamical Systems
Tue 10 Apr / 3:30 / EAA1100 Ladislav Stacho, Math, SFU Edge Disjoint Cycles Through Prescribed Vertices
Tue 17 Apr / 3:30 / EAA1100 Nancy Neudauer, Pacific Lutheren U. Bicircular Matroids and Transversal Presentations