Combinatorial reciprocity for Monotone Triangles
Combinatorial reciprocity for Monotone Triangles
复制标题
单调三角形的组合互易
DOI:
10.1016/j.jcta.2013.04.002
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发表时间:
2011
期刊:
影响因子:
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通讯作者:
L. Riegler
中科院分区:
文献类型:
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作者:
Ilse Fischer;L. Riegler
Abstract The number of Monotone Triangles with bottom row k 1< k 2<⋯< k n is given by a polynomial α (n; k 1,…, k n) in n variables. The evaluation of this polynomial at weakly decreasing sequences k 1⩾ k 2⩾⋯⩾ k n turns out to be interpretable as signed enumeration of new combinatorial objects called Decreasing Monotone Triangles. There exist surprising connections between the two classes of objects–in particular it is shown that α (n; 1, 2,…, n)= α (2 n; n, n, n− 1, n− 1,…, 1, 1). In perfect analogy to the correspondence between Monotone Triangles and Alternating Sign Matrices, the set of Decreasing Monotone Triangles with bottom row (n, n, n− 1, n− 1,…, 1, 1) is in one-to-one correspondence with a certain set of ASM-like matrices, which also play an important role in proving the claimed identity algebraically. Finding a bijective proof remains an open problem.
DOI:
10.1137/130944849
发表时间:
2014
期刊:
SIAM J. Discret. Math.
影响因子:
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作者:
Katharina Jochemko;Raman Sanyal
通讯作者:
Raman Sanyal