The coboundary polynomial  is a bivariate graph polynomial which can be expressed
 in terms of the Tutte polynomial 
 of a graph 
 by
where 
 is the connected component count and 
 is the vertex count of a
 graph 
 (Martin and Reiner 2005; Ardila 2007).
The coboundary polynomial provides a particularly concise way of expression generating functions for the Tutte polynomial of a complete
 graph 
 or complete bipartite graph 
.