A GROUP SUM INEQUALITY AND ITS APPLICATION TO POWER GRAPHS

作者:Curtin Brian*; Pourgholi G R
来源:Bulletin of the Australian Mathematical Society, 2014, 90(3): 418-426.
DOI:10.1017/S0004972714000434

摘要

Let G be a finite group of order n, and let C-n be the cyclic group of order n. For g is an element of G, let o(g) denote the order of g. Let phi denote the Euler totient function. We show that Sigma(g is an element of Cn) phi(o(g)) %26gt;= Sigma(g is an element of G) phi(o(g)), with equality if and only if G is isomorphic to Cn. As an application, we show that among all finite groups of a given order, the cyclic group of that order has the maximum number of bidirectional edges in its directed power graph.

  • 出版日期2014-12