Depth and Stanley depth of the edge ideals of the powers of paths and cycles

Let k be a positive integer. We compute depth and Stanley depth of the quotient ring of the edge ideal associated to the k^th power of a path on n vertices. We show that both depth and Stanley depth have the same values and can be given in terms of k and n. If n≣0, k + 1, k + 2, . . . , 2k(mod(2k + 1)), then we give values of depth and Stanley depth of the quotient ring of the edge ideal associated to the k^th power of a cycle on n vertices and tight bounds otherwise, in terms of n and k. We also compute lower bounds for the Stanley depth of the edge ideals associated to the k^th power of a path and a cycle and prove a conjecture of Herzog for these ideals.