The minimum Q-index of strongly connected bipartite digraphs with complete bipartite subdigraphs

Weige Xi, Ligong Wang

Let ${\mathcal{G}}_{n,p,q}$ denote the set of strongly connected bipartite digraphs on $n$ vertices which contain a complete bipartite subdigraph $\overleftrightarrow{K_{p,q}}$, wher…