On the dual canonical and Kazhdan-Lusztig bases and 3412-, 4231-avoiding permutations
On the dual canonical and Kazhdan-Lusztig bases and 3412-, 4231-avoiding permutations
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DOI:
10.1016/j.jpaa.2007.09.007
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发表时间:
2008-05
影响因子:
0.8
通讯作者:
Marcos Skandera
中科院分区:
文献类型:
--
作者:
Marcos Skandera
Using Du’s characterization of the dual canonical basis of the coordinate ring O(GL(n,C)), we express all elements of this basis in terms of immanants. We then give a new factorization of permutations w avoiding the patterns 3412 and 4231, which in turn yields a factorization of the corresponding Kazhdan–Lusztig basis elements Cw′(q) of the Hecke algebra Hn(q). Using the immanant and factorization results, we show that for every totally nonnegative immanant Immf(x) and its expansion ∑dwImmw(x) with respect to the basis of Kazhdan–Lusztig immanants, the coefficient dwmust be nonnegative when w avoids the patterns 3412 and 4231.