We prove that in a graph of order n and minimum degree d, the mean distance Β΅ must satisfy This asymptotically confirms, and improves, a conjecture of the computer program GRAFFITI. The result is close to optimal; examples show that for any d, Β΅ may be larger than n/(d + 1).
Average distance, minimum degree, and spanning trees
β Scribed by Dankelmann, Peter; Entringer, Roger
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 218 KB
- Volume
- 33
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
The average distance Β΅(G) of a connected graph G of order n is the average of the distances between all pairs of vertices of G, i.e., Β΅(G) = ( n 2 ) -1 {x,y}βV (G) d G (x, y), where V (G) denotes the vertex set of G and d G (x, y) is the distance between x and y. We prove that every connected graph of order n and minimum degree Ξ΄ has a spanning tree T with average distance at most n Ξ΄+1 + 5. We give improved bounds for K 3 -free graphs, C 4 -free graphs, and for graphs of given girth.
π SIMILAR VOLUMES
## Abstract Degree conditions on the vertices of a __t__βtough graph __G__ (1ββ€βtβ<β3) are presented which ensure the existence of a spanning cubic subgraph in __G__. These conditions are best possible to within a small additive constant for every fixed rational __t__ β[1,4/3)βͺ[2,8/3). Β© 2003 Wiley
The electronic version has been replaced with the correct figures; the corrected print version follows. The article originally posted in Wiley InterScience is available from the publisher should anyone require access to it. We regret any inconvenience this may have caused.
95-99 mistakenly attributes the computer program GRAFFITI to Fajtlowitz and Waller, instead of just Fajtlowitz. (Our apologies to Siemion Fajtlowitz.) Note also that one of the ''flaws'' we note for Conjecture 62 (that it was made for graphs regular of degree d, vice graphs of minimum degree d) was