Distance-regularised graphs are distance-regular or distance-biregular
β Scribed by Chris D Godsil; John Shawe-Taylor
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 506 KB
- Volume
- 43
- Category
- Article
- ISSN
- 0095-8956
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π SIMILAR VOLUMES
We describe here some properties of a class of graphs which extends the class of distance regular graphs: our graphs are bipartite and for cach vertex there exists an intersection array depending on the stable component of the vertex. Thus our graphs arc to distance regular graphs as bipartite regul
Let β« be a distance-regular graph with l (1 , a 1 , b 1 ) Ο 1 and c s Ο© 1 Ο 1 for some positive integer s . We show the existence of a certain distance-regular graph of diameter s , containing given two vertices at distance s , as a subgraph in β« .
Let β« be a distance-regular graph with a 1 ΟΎ 0 , r Ο max Ν j 3 ( c j , a j , b j ) Ο ( c 1 , a 1 , b 1 ) Ν Ρ 2 and a i Ο a 1 c i , for 1 Ρ i Ρ 2 r . Take any u and in β« at distance r Ο© 1 . We show that there exists a collinearity graph of a generalized 2( r Ο© 1)-gon of order ( a 1 Ο© 1 , c r Ο© 1 Οͺ 1)
In this paper we give a sufficient condition for the existence of a strongly closed subgraph which is (c q + a q )-regular of diameter q containing a given pair of vertices at distance q in a distance-regular graph. Moreover we show that a distance-regular graph with r = max{ j | (c j , a j , b j )