000K utf8 0100 827726732 0500 Ou 1100 $c2005 1500 eng 2050 urn:nbn:de:gbv:ilm1-2020200102 2051 10.7151/dmgt.1256 2240 3000 Harant, Jochen 3010 Henning, Mike 4000 On double domination in graphs [Harant, Jochen] 4060 6 Seiten 4209 In a graph G, a vertex dominates itself and its neighbors. A subset S ⊆ V(G) is a double dominating set of G if S dominates every vertex of G at least twice. The minimum cardinality of a double dominating set of G is the double domination number γ ×2(G). A function f(p) is defined, and it is shown that γ ×2(G) = minf(p), where the minimum is taken over the n-dimensional cube Cn = {p = (p1,…,pn) | pi ∈ IR, 0 ≤ pi ≤ 1,i = 1,…,n}. Using this result, it is then shown that if G has order n with minimum degree δ and average degree d, then γ×2(G) ≤ ((ln(1+d)+lnδ+1)/δ)n. 4950 https://doi.org/10.7151/dmgt.1256$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:gbv:ilm1-2020200102$xR$3Volltext$534 4961 http://uri.gbv.de/document/gvk:ppn:827726732 5051 510 5550 average degree 5550 bounds 5550 double domination 5550 probabilistic method