Universal minimal total dominating functions in graphs. (English) Zbl 0804.90122

Cockayne, E. J.; Mynhardt, C. M.; Yu, Bo

Networks 24, No. 2, 83-90 (1994).

Summary: A total dominating function (TDF) of a graph \(G= (V,E)\) is a function \(f: V\to [0,1]\) such that for each \(v\in V\), \(\sum_{u\in N(v)}f(u)\geq 1\) [where \(N(v)\) denotes the open neighborhood of vertex \(v\)]. Integer- valued TDFs are precisely characteristic functions of total dominating sets of \(G\). Convex combinations of two TDFs are themselves TDFs but convex combinations of minimal TDFs (MTDFs) are not necessarily minimal. This paper is concerned with the existence of a universal MTDF in a graph, i.e., a MTDF \(g\) such that convex combinations of \(g\) and any other MTDF are themselves minimal.

MSC:

90C35

Programming involving graphs or networks

Keywords:

total dominating function; universal MTDF in a graph; convex combinations

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