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CV: Born 1961 in Germany.
Thomas Wieder: Generation of All Possible Multiselections from a Multiset, Progress in Applied Mathematics 2(1) (2011), 61-66.
Thomas Wieder: The number of certain rankings and hierarchies formed from labeled or unlabeled elements and sets, APPLIED MATHEMATICAL SCIENCES 3(55) (2009), 2707-2724.
Thomas Wieder: The Number Of Certain k-Combinations Of An n-Set, Applied Mathematical E-Notes 8 (2008), 42-52.
N. J. A. Sloane and T. Wieder: The Number of Hierarchical Orderings, Order 21(1) (2004), 83-89.
Links to some of my documents and programs:
Maple program multichoose for multiselections from multisets:
Maple program multiselection for multiselections from multisets:
Maple program enum for generation of integer matrices with given row and column sums:
Fortran program OPTM0.f95 for for selection of an optimal submultiset from a multiset:
Yet another Maple program for multiselections from multisets (one after the other):