s***i 发帖数: 49 | | v********e 发帖数: 1058 | 2 Let X = (V, E) be a graph. A parttition \pi of V(X) with cells C_1, ..., C_r
is equitable if the number of neighbours in C_j of a vertex u in C_i is a
constant b_ij, independent of u. An equivalent definition is that the
subgraph of X induced by each cell is regular, and the edges joining any two
distinct cells form a semiregular bipartite graph. The directed graph with
the r cells of \pi as its vertices and b_ij arcs from the i-th to the j-th
cells of \pi is called the quotient of X over \pi.
【在 s***i 的大作中提到】 : 能不能解释一下,google不到。。。。
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