Covering Finite Groups by Subset Products

H.V. Chen1, A.Y. M.Chin2
1Department of Mathematical and Actuarial Sciences Faculty of Engineering and Science Universiti Tunku Abdul Rahman Jalan Genting Kelang, 53300 Kuala Lumpur Malaysia
2Institute of Mathematical Sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia

Abstract

Let \(G\) be a finite group and let \(S\) be a nonempty subset of \(G\). For any positive integer \(k\), let \(S^k\) be the subset product given by the set \(\{s_1 \cdots s_k \mid s_1, \ldots, s_k \in S\}\). If there exists a positive integer \(n\) such that \(S^n = G\), then \(S\) is said to be exhaustive. Let \(e(S)\) denote the smallest positive integer \(n\), if it exists, such that \(S^n = G\). We call \(e(S)\) the exhaustion number of the set \(S\). If \(S^n \neq G\) for any positive integer \(n\), then \(S\) is said to be non-exhaustive. In this paper, we obtain some properties of exhaustive and non-exhaustive subsets of finite groups.