A generalization of a recent result of Tomescu ( 1993) is presented. The method is purely combinatorial and is based on the theory of species of several variables.
On the number of irreducible coverings by edges of complete bipartite graphs
✍ Scribed by Ioan Tomescu
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 102 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0012-365X
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✦ Synopsis
In this paper it is proved that the exponential generating function of the numbers, denoted by N(p, q), of irreducible coverings by edges of the vertices of complete bipartite graphs Kp.q equals exp(xe r + ye x -x -y -xy) -t.
📜 SIMILAR VOLUMES
The aim of this paper is to determine the maximal number of induced K(t, t) subgraphs in graphs of given order and in graphs of given size. Given a graph G and a natural number t, denote by ft(G) the number of induced subgraphs of G isomorphic to K(t, t). Our notation is that of ; in particular, K(
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