Triangle wave   

A wave form in the shape of a triangle which contains only odd harmonics.   

the harmonics above the fundamental donít have as much energy as those of a pulse wave

triangle
 
 

 
The amplitude of a specific harmonic (relative to the amplitude of the fundamental) is square of the inverse of its harmonic number:  
1/n**2 where n is the partial number. Thus the fifth harmonic has 1/25th the amplitude of the fundamental.