Parallelogram-free distance-regular graphs having completely regular strongly regular subgraphs
نویسندگان
چکیده
منابع مشابه
Parallelogram-free distance-regular graphs having completely regular strongly regular subgraphs
Let = (X,R) be a distance-regular graph of diameter d . A parallelogram of length i is a 4-tuple xyzw consisting of vertices of such that ∂(x, y)= ∂(z,w)= 1, ∂(x, z)= i, and ∂(x,w)= ∂(y,w)= ∂(y, z)= i− 1. A subset Y of X is said to be a completely regular code if the numbers πi,j = | j (x)∩ Y | (i, j ∈ {0,1, . . . , d}) depend only on i = ∂(x,Y ) and j . A subset Y of X is said to be strongly c...
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ژورنال
عنوان ژورنال: Journal of Algebraic Combinatorics
سال: 2009
ISSN: 0925-9899,1572-9192
DOI: 10.1007/s10801-009-0167-2