Bipartite graphs related to mutually disjoint S-permutation matrices
نویسنده
چکیده
Some numerical characteristics of bipartite graphs in relation to the problem of finding all disjoint pairs of S-permutation matrices in the general n × n case are discussed in this paper. All bipartite graphs of the type g = 〈Rg ∪ Cg, Eg〉, where |Rg| = |Cg | = 2 or |Rg| = |Cg | = 3 are provided. The cardinality of the sets of mutually disjoint S-permutation matrices in both the 4× 4 and 9× 9 cases are calculated. Keyword:Bipartite graph, Binary matrix, S-permutation matrix, Disjoint matrices, Sudoku MSC[2010] code: 05C30, 05B20, 05C50
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