Intersection cohomology of the symmetric reciprocal plane
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چکیده
We compute the Kazhdan-Lusztig polynomial of the uniform matroid of rank n − 1 on n elements by proving that the coefficient of t is equal to the number of ways to choose i non-intersecting chords in an (n − i + 1)-gon. We also show that the corresponding intersection cohomology group is isomorphic to the irreducible representation of Sn associated to the partition [n− 2i, 2, . . . , 2].
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تاریخ انتشار 2015