{ "id": "2211.14093", "version": "v1", "published": "2022-11-25T13:24:29.000Z", "updated": "2022-11-25T13:24:29.000Z", "title": "Skew hook Schur functions and the cyclic sieving phenomenon", "authors": [ "Nishu Kumari" ], "comment": "13 pages, 2 figures", "categories": [ "math.CO", "math.RT" ], "abstract": "Fix an integer $t \\geq 2$ and a primitive $t^{\\text{th}}$ root of unity $\\omega$. We consider the specialized skew hook Schur polynomial $\\text{hs}_{\\lambda/\\mu}(X,\\omega X,\\dots,\\omega^{t-1}X/Y,\\omega Y,\\dots,\\omega^{t-1}Y)$, where $\\omega^k X=(\\omega^k x_1, \\dots, \\omega^k x_n)$, $\\omega^k Y=(\\omega^k y_1, \\dots, \\omega^k y_m)$ for $0 \\leq k \\leq t-1$. We characterize the skew shapes $\\lambda/\\mu$ for which the polynomial vanishes and prove that the nonzero polynomial factorizes into smaller skew hook Schur polynomials. Then we give a combinatorial interpretation of $\\text{hs}_{\\lambda/\\mu}(1,\\omega^d,\\dots,\\omega^{d(tn-1)}/1,\\omega^d,\\dots,\\omega^{d(tm-1)})$, for all divisors $d$ of $t$, in terms of ribbon supertableaux. Lastly, we use the combinatorial interpretation to prove the cyclic sieving phenomenon on the set of semistandard supertableaux of shape $\\lambda/\\mu$ for odd $t$. Using a similar proof strategy, we give a complete generalization of a result of Lee--Oh (arXiv: 2112.12394, 2021) for the cyclic sieving phenomenon on the set of skew SSYT conjectured by Alexandersson--Pfannerer--Rubey--Uhlin (Forum Math. Sigma, 2021).", "revisions": [ { "version": "v1", "updated": "2022-11-25T13:24:29.000Z" } ], "analyses": { "subjects": [ "05E18", "05E05", "05E10" ], "keywords": [ "cyclic sieving phenomenon", "skew hook schur functions", "smaller skew hook schur polynomials", "specialized skew hook schur polynomial", "combinatorial interpretation" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }