The Signed Total Domination Number of Graphs

Mingjing Gao1,2, Erfang Shan3,2
1Department of Mathematics and physics, Hebei Normal University of science and Technology, Hebei 066004
2Department of Mathematics, Shanghai University, Shanghai 200444, China
3Department of Logistics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong

Abstract

Let \(G\) be a graph on \(2n\) vertices with minimum degree \(r\). We show that there exists a two-coloring of the vertices of \(G\) with colors \(-1\) and \(+1\), such that all open neighborhoods contain more \(+1\)’s than \(-1\)’s, and altogether the number of \(+1\)’s does not exceed the number of \(-1\)’s by more than \(O(\frac{n}{\sqrt{n}})\).