𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Antipodal Distance Transitive Covers of Complete Graphs

✍ Scribed by C.D. Godsil; R.A. Liebler; C.E. Praeger


Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
352 KB
Volume
19
Category
Article
ISSN
0195-6698

No coin nor oath required. For personal study only.

✦ Synopsis


A distance-transitive antipodal cover of a complete graph K n possesses an automorphism group that acts 2-transitively on the fibres. The classification of finite simple groups implies a classification of finite 2-transitive permutation groups, and this allows us to determine all possibilities for such a graph. Several new infinite families of distance-transitive graphs are constructed.


πŸ“œ SIMILAR VOLUMES


Antipodal Distance-transitive Covers of
✍ A.A. Ivanov; Robert A. Liebler; Tim Penttila; Cheryl E. Praeger πŸ“‚ Article πŸ“… 1997 πŸ› Elsevier Science 🌐 English βš– 480 KB

This paper completes the classification of antipodal distance-transitive covers of the complete bipartite graphs K k , k , where k Ρƒ 3 . For such a cover the antipodal blocks must have size r Ρ€ k . Although the case r Ο­ k has already been considered , we give a unified treatment of r Ρ€ k . We use d

Distance-Regular Graphs withbt=1 and Ant
✍ Makoto Araya; Akira Hiraki; Aleksandar JuriΕ‘iΔ‡ πŸ“‚ Article πŸ“… 1996 πŸ› Elsevier Science 🌐 English βš– 239 KB

Let 1 be a distance-regular graph of diameter d and valency k>2. If b t =1 and 2t d, then 1 is an antipodal double-cover. Consequently, if f >2 is the multiplicity of an eigenvalue of the adjacency matrix of 1 and if 1 is not an antipodal doublecover then d 2f&3. This result is an improvement of God

On 2-Arc-Transitive Covers of Complete G
✍ Shao-fei Du; Dragan MaruΕ‘ič; Adrian O Waller πŸ“‚ Article πŸ“… 1998 πŸ› Elsevier Science 🌐 English βš– 282 KB

Regular covers of complete graphs which are 2-arc-transitive are investigated. A classification is given of all such graphs whose group of covering transformations is either cyclic or isomorphic to Z p \_Z p , where p is a prime and whose fibrepreserving subgroup of automorphisms acts 2-arc-transiti

Distance-regular Graphs with b2=1 and An
✍ Makoto Araya; Akira Hiraki; Aleksandar JurisiΔ‡ πŸ“‚ Article πŸ“… 1997 πŸ› Elsevier Science 🌐 English βš– 234 KB

We show that a distance-regular graph of valency k ΟΎ 2 is antipodal , if b 2 Ο­ 1 . This answers Problem (i) on p . 182 of Brouwer , Cohen and Neumaier [4] .

Antipodal distance-regular graphs of dia
✍ Tilla Schade πŸ“‚ Article πŸ“… 1999 πŸ› John Wiley and Sons 🌐 English βš– 179 KB πŸ‘ 2 views

An antipodal distance-regular graph of diameter four or five is a covering graph of a connected strongly regular graph. We give existence conditions for these graphs and show for some types of strongly regular graphs that no nontrivial covers exist.

Bipartite Q-Polynomial Quotients of Anti
✍ John S. Caughman IV πŸ“‚ Article πŸ“… 1999 πŸ› Elsevier Science 🌐 English βš– 91 KB

Let 1 denote a bipartite Q-polynomial distance-regular graph with diameter D 4. We show that 1 is the quotient of an antipodal distance-regular graph if and only if one of the following holds. (i) 1 is a cycle of even length. (ii) 1 is the quotient of the 2D-cube. 1999 Academic Press \* , ..., %\