Graphs which are both H_1 and H_2-decomposable
A graph G is said to be H-decomposable if there exists a collection of
subgraphs of G, each isomorphic to H, which partition the edge set of
G. If G is H-decomposable, we say that H|G. Given two graphs
H_1 and H_2, for which values q does there exist a graph G
having q edges such that H_1|G and H_2|G? The problem will
be considered for the cases when H_1 and H_2 are both cycles
and when H_1 and H_2 are both complete graphs.