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Central Delannoy Numbers and Balanced Cohen- Macaulay Complexes
Gábor Hetyei
Department of Mathematics and Statistics, The University of North Carolina at Charlotte, Charlotte, NC 28223, USA
Annals of Combinatorics 10 (4) p.443-462 December, 2006
AMS Subject Classification: 13F55, 05A15, 16E65, 33C45
We introduce a new join operation on colored simplicial complexes that preserves the Cohen-Macaulay property. An example of this operation puts the connection between the central Delannoy numbers and Legendre polynomials in a wider context.
Keywords: balanced simplicial complex, Delannoy numbers, Cohen-Macaulay property


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