Restricted lonesum matrices

Lonesum matrices are matrices that are uniquely reconstructible from their row and column sum vectors. These matrices are enumerated by the poly-Bernoulli numbers; a sequence related to the multiple zeta values with a rich literature in number theory. Lonesum matrices are in bijection with many other combinatorial objects: several permutation classes, matrix classes, acyclic orientations in complete bipartite graphs etc. Motivated of these facts, we study in this paper lonesum matrices with restriction on the number of columns and rows of the same type. Keywords: enumeration, poly-Bernoulli numbers, restricted Stirling numbers, lonesum matrices MSC: 05A05, 05A15, 05A18, 05A1

Restricted lonesum matrices

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