Staircase Skew Schur Functions Are Schur P -positive
نویسندگان
چکیده
We prove Stanley’s conjecture that, if δn is the staircase shape, then the skew Schur functions sδn/μ are non-negative sums of Schur P -functions. We prove that the coefficients in this sum count certain fillings of shifted shapes. In particular, for the skew Schur function sδn/δn−2 , we discuss connections with Eulerian numbers and alternating permutations.
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