On the acyclic point-connectivity of the n-cube

Abstract

The acyclic point-connectivity of a graph G, denoted α(G), is the minimum number of points whose removal from G results in an acyclic graph. In a 1975 paper, Harary stated erroneously that α(Qn)=2n−1−1 where Qn denotes the n-cube. We prove that for n>4, 7⋅2n−4≤α(Qn)≤2n−1−2n−y−2, where y=[log2(n−1)]. We show that the upper bound is obtained for n≤8 and conjecture that it is obtained for all n.