{ "id": "1908.08502", "version": "v1", "published": "2019-08-22T17:17:17.000Z", "updated": "2019-08-22T17:17:17.000Z", "title": "A Pieri rule for Demazure characters of the general linear group", "authors": [ "Sami Assaf", "Danjoseph Quijada" ], "comment": "65 pages, 28 figures", "categories": [ "math.CO" ], "abstract": "The Pieri rule is a nonnegative, multiplicity-free formula for the Schur function expansion of the product of an arbitrary Schur function with a single row Schur function. Key polynomials are characters of Demazure modules for the general linear group that generalize the Schur function basis of symmetric functions to a basis of the full polynomial ring. We prove a nonsymmetric generalization of the Pieri rule by giving a cancellation-free, multiplicity-free formula for the key polynomial expansion of the product of an arbitrary key polynomial with a single part key polynomial. Our proof is combinatorial, generalizing the Robinson--Schensted--Knuth insertion algorithm on tableaux to an insertion algorithm on Kohnert diagrams.", "revisions": [ { "version": "v1", "updated": "2019-08-22T17:17:17.000Z" } ], "analyses": { "keywords": [ "general linear group", "pieri rule", "demazure characters", "polynomial", "multiplicity-free formula" ], "note": { "typesetting": "TeX", "pages": 65, "language": "en", "license": "arXiv", "status": "editable" } } }