Potentially \(K_{r+1}^{-p}\)-Graphic Sequences

Jian-Hua Yin1, Jiong-Sheng Li2
1Department of Applied Mathematics, College of Information Science and Technology, Hainan University, Haikou, Hainan 570228, China.
2Department of Mathematics University of Science and Technology of China, Hefei, Anhui 230026, China.

Abstract

Let \(0 \leq p \leq [\frac{r+1}{2}]\) and \(\sigma(K_{r+1}^{-p},n)\) be the smallest even integer such that each \(n\)-term graphic sequence with term sum at least \(\sigma(K_{r+1}^{-p},n)\) has a realization containing \(K_{r+1}^{-p}\) as a subgraph, where \(K_{r+1}^{-p}\) is a graph obtained from a complete graph \(K_{r+1}\) on \(r+1\) vertices by deleting \(p\) edges which form a matching. In this paper, we determine \(\sigma(K_{r+1}^{-p},n)\) for \(r \geq 2, 1 \leq p \leq [\frac{r+1}{2}]\) and \(n \geq 3r + 3\). As a corollary, we also determine \(\sigma(K_{1^*,2^t}n)\) for \(t \geq 1\) and \(n \geq 3s + 6t\), where \(K_{1^*,2^t}\) is an \(r_1\times r_2\times \ldots \times r_{s+t}\) complete \((s + t)\)-partite graph with \(r_1 = r_2 = \ldots = r_s = 1\) and \(r_{s+1} = r_{s+2} = \ldots = r_{s+t} = 2\) and \(\sigma(K_{1^*,2^t},n)\) is the smallest even integer such that each \(n\)-term graphic sequence with term sum at least \(\sigma(K_{1^*,2^t},n)\) has a realization containing \(K_{1^*,2^t}\) as a subgraph.