{ "id": "2408.12386", "version": "v1", "published": "2024-08-22T13:27:22.000Z", "updated": "2024-08-22T13:27:22.000Z", "title": "Preservation of inequalities under Hadamard products", "authors": [ "Petter Brändén", "Luis Ferroni", "Katharina Jochemko" ], "comment": "21 pages", "categories": [ "math.CO" ], "abstract": "Wagner (1992) proved that the Hadamard product of two P\\'olya frequency sequences that are interpolated by polynomials is again a P\\'olya frequency sequence. We study the preservation under Hadamard products of related properties of significance in combinatorics. In particular, we show that ultra log-concavity, $\\gamma$-positivity, and interlacing symmetric decompositions are preserved. Furthermore, we disprove a conjecture by Fischer and Kubitzke (2014) concerning the real-rootedness of Hadamard powers.", "revisions": [ { "version": "v1", "updated": "2024-08-22T13:27:22.000Z" } ], "analyses": { "keywords": [ "hadamard product", "polya frequency sequence", "preservation", "inequalities", "ultra log-concavity" ], "note": { "typesetting": "TeX", "pages": 21, "language": "en", "license": "arXiv", "status": "editable" } } }