On the Automorphism Group of Token Graphs of Complete Bipartite Graphs

Let G be a graph of order n and let k∈{1,2,…,n-1}. The k-token graph of G is the graph, whose vertices are all the k-subsets of vertices of G, where two such k-sets are adjacent whenever their symmetric difference is an edge of G. In this paper, we determine the automorphism group of the k-token graph of the complete bipartite graph K_m,n.