On The Number Of Unlabeled Bipartite Graphs
نویسندگان
چکیده
Let I and O denote two sets of vertices, where I ∩ O = Φ, |I| = n, |O| = r, and Bu(n, r) denote the set of unlabeled graphs whose edges connect vertices in I and O. It is shown that the following two-sided equality holds. ( r+2n−1 r ) n! ≤ |Bu(n, r)| ≤ 2 ( r+2n−1 r )
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تاریخ انتشار 2017