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Distance-regular Subgraphs in a Distance-regular Graph, IV

✍ Scribed by Akira Hiraki

Publisher: Elsevier Science
Year: 1997
Tongue: English
Weight: 280 KB
Volume: 18
Category: Article
ISSN: 0195-6698
DOI: 10.1006/eujc.1996.0128

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✦ Synopsis

Let ⌫ be a distance-regular graph with a 1 Ͼ 0 , r ϭ max ͕ j 3 ( c j , a j , b j ) ϭ ( c 1 , a 1 , b 1 ) ͖ у 2 and a i ϭ a 1 c i , for 1 р i р 2 r . Take any u and in ⌫ at distance r ϩ 1 . We show that there exists a collinearity graph of a generalized 2( r ϩ 1)-gon of order ( a 1 ϩ 1 , c r ϩ 1 Ϫ 1) containing u and as a subgraph in ⌫ .

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