ArticleOriginal scientific text
Title
Classes of hypergraphs with sum number one
Authors 1
Affiliations
- Institute of Mathematics, Medical University of Lübeck, Wallstraße 40, 23560 Lübeck, Germany
Abstract
A hypergraph ℋ is a sum hypergraph iff there are a finite S ⊆ ℕ⁺ and d̲,d̅ ∈ ℕ⁺ with 1 < d̲ < d̅ such that ℋ is isomorphic to the hypergraph where V = S and . For an arbitrary hypergraph ℋ the sum number(ℋ ) is defined to be the minimum number of isolatedvertices such that is a sum hypergraph. For graphs it is known that cycles Cₙ and wheels Wₙ have sum numbersgreater than one. Generalizing these graphs we prove for the hypergraphs ₙ and ₙ that under a certain condition for the edgecardinalities (ₙ)= (ₙ)=1
Keywords
hypergraphs, sum number, vertex labelling
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