## Abstract The odd girth of a graph __G__ gives the length of a shortest odd cycle in __G.__ Let __f(k,g)__ denote the smallest __n__ such that there exists a __k__βregular graph of order __n__ and odd girth __g.__ The exact values of __f(k,g)__ are determined if one of the following holds: __k__
Regular graphs with prescribed chromatic number
β Scribed by L. Caccetta; N. J. Pullman
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 200 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
We determine the minimum number of edges in a regular connected graph on n vertices, containing a complete subgraph of order k β€ n/2. This enables us to confirm and strengthen a conjecture of P. ErdΓΆs on the existence of regular graphs with prescribed chromatic number.
π SIMILAR VOLUMES
The odd girth of a graph \(G\) gives the length of a shortest odd cycle in \(G\). Let \(f(k, g)\) denote the smallest \(n\) such that there exists a \(k\)-regular graph of order \(n\) and odd girth \(g\). It is known that \(f(k, g) \geqslant k g / 2\) and that \(f(k, g)=k g / 2\) if \(k\) is even. T
## Abstract The __r__βacyclic edge chromatic number of a graph is defined to be the minimum number of colors required to produce an edge coloring of the graph such that adjacent edges receive different colors and every cycle __C__ has at least min(|__C__|, __r__) colors. We show that (__r__βββ2)__d
The distance graph G(D) with distance set D={d 1 , d 2 , ...} has the set Z of integers as vertex set, with two vertices i, j Β₯ Z adjacent if and only if |i -j| Β₯ D. We prove that the chromatic number of G(D) is finite whenever inf{d i+1 /d i } > 1 and that every growth speed smaller than this admit
## Abstract It was only recently shown by Shi and Wormald, using the differential equation method to analyze an appropriate algorithm, that a random 5βregular graph asymptotically almost surely has chromatic number at most 4. Here, we show that the chromatic number of a random 5βregular graph is as