Title An Optimal Binding Number Condition for Bipancyclism

Let G = (V1, V2, E) be a balanced bipartite graph with 2n vertices. The bipartite binding number of G, denoted by B(G), is defined to be n if G = Kn,n and mini∈ {1,2} min ∅ =S⊆Vi |N(S)| 3/2 and n ≥ 139, then G is bipancyclic; the bound 3/2 is best possible in the sense that there exist infinitely many balanced bipartite graphs G that have B(G) = 3/2 but are not Hamiltonian.