arXiv math/05081532005-08-08math.CO

On Expected Factors in Reduced Decompositions in Type B

Bridget Eileen Tenner

备注：: 8 pages; 4 figures

英文摘要：

The expected number of Yang-Baxter moves appearing in a reduced decomposition of the longest element of the Coxeter group of type B_n is computed to be 2-4/n. For the same element, the expected number of 0101 or 1010 factors appearing in a reduced decomposition is 2/(n^2-2).

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