A graphon is a symmetric measurable function W:[0,1]2→[0,1]. Given a graphon W and a finite graph H=(V(H),E(H)), the homomorphism density t(H,W) is defined as
t(H,W)=∫[0,1]V(H){v,w}∈E(H)∏W(xv,xw)v∈V(H)∏dxv.
For a finite bipartite graph H, let C(H) denote the least constant for which
t(H,W)≥t(K2,W)C(H)
holds for all graphons W, where K2 is the complete graph on two vertices. What is C(H)?