In this paper we present a short algebraic proof for a generalization of a formula of R. Penrose, Some applications of negative dimensional tensors, in: Combinatorial Mathematics and its Applications Welsh (ed.), Academic Press, 1971, pp. 221-244 on the number of 3-edge colorings of a plane cubic gr
The number of edge 3-colorings of a planar cubic graph as a permanent
β Scribed by David E. Scheim
- Publisher
- Elsevier Science
- Year
- 1974
- Tongue
- English
- Weight
- 370 KB
- Volume
- 8
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
In this paper, we establish that the number of edge 3-colorings of a finite planar cubic graph G, i.e., 3-colorings of its interchange graph H, is equal to 2*lPermanent(A)l, where N is the number of edges of G, and A is the 2N X 2iV square matrix formed by repeating each row of the N X 2N vertexdirected edge incidence matrix of H (with an arbitrary orientation). As the number of 4-colorings of a finite maximal (fully triangulated) planar graph is equal to four times the number of edge 3-colorings of its planar cubic dual, this result gives a formula for the number of 4-colorings of a finite maximal planar graph. * **
π SIMILAR VOLUMES
## Abstract We prove that for any planar graph __G__ with maximum degree Ξ, it holds that the chromatic number of the square of __G__ satisfies Ο(__G__^2^)ββ€β2Ξβ+β25. We generalize this result to integer labelings of planar graphs involving constraints on distances one and two in the graph. Β© 2002
We consider the problem: Characterize the edge orienta,tions of a finite graph with a maximum number of pairs of oppositely oriented edges. The probiem is solved for finite cubic graphs.
Let 9 denote the family of simple undirected graphs on u vertices having e edges ( ( u , el-graphs) and P(A, G ) be the chromatic polynomial of a graph G. For the given integers u, e, A, let f b , e, A) denote the greatest number of proper colorings in A or less colors that a (u, e)-graph G can have