Number of Right Ideals and a q-analogue of Indecomposable Permutations

作者：Bacher Roland^*; Reutenauer Christophe^*

来源：Canadian Journal of Mathematics, 2016, 68(3): 481-503.

DOI：10.4153/CJM-2016-004-8

• permutation
• indecomposable permutation
• subgroups of free groups

We prove that the number of right ideals of codimension n in the algebra of noncommutative Laurent polynomials in two variables over the finite field F-q is equal to
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where the sum is over all indecomposable permutations in Sn+1 and where inv(theta) stands for the number of inversions of theta.

• 出版日期2016-6