## G, let a(G? maximum number k such that G contains a circuit with k Theorem. For any graph G with minimum valency n 2 3, a(G) z=:$(n + l)(n -2). If the equality holds and :3 is connected, then either G is isomorphic to K,,, or G is separable and each of its terminal blocks is isomorphic to K,+,
The maximum number of diagonals of a cycle in a block and its extremal graphs
β Scribed by Feng Tian; Wenan Zang
- Publisher
- Elsevier Science
- Year
- 1991
- Tongue
- English
- Weight
- 739 KB
- Volume
- 89
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
Tian, F. and W. Zang, The maximum number of diagonals of a cycle in a block and its extremal graphs, Discrete Mathematics 89 (1991) 51-63.
In this paper we show that if G is a 2-connected graph having minimum degree n such that IV(G)1 L 2n + 1, then there exists a cycle in G having more than n(n -2) diagonals, unless G is K n,mr m >n or the Petersen graph. So the conjecture posed by Gupta, Kahn and Robertson is settled completely.
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