出典:Wikipedia
出典:『Wikipedia』 (2011/05/31 09:14 UTC 版)
In the mathematical field of graph theory, given a distance-regular graph G of diameter d, by definition there are integers bi and ci such that given any two vertices x and y in G at distance i, y has bi neighbours at distace i + 1 from x and ci neighbours at distance i − 1 from x. The sequence {b0, ..., bd−1;c1, ..., cd} is called the intersection array of G.