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
On the number of colorings of a snark minus an edge
β Scribed by Richard C. Bradley
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 93 KB
- Volume
- 51
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
For a given snark G and a given edge e of G, let (G; e) denote the nonnegative integer such that for a cubic graph conformal to G Γ feg, the number of Tait colorings with three given colors is 18 Γ (G; e). If two snarks G 1 and G 2 are combined in certain well-known simple ways to form a snark G, there are some connections between (G 1 ; e 1 ), (G 2 ; e 2 ), and (G; e) for appropriate edges e 1 , e 2 , and e of G 1 , G 2 , and G. As a consequence, if j and k are each a nonnegative integer, then there exists a snark G with an edge e such that (G; e) ΒΌ 2 j Γ 3 k .
π SIMILAR VOLUMES
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