{ "id": "1312.5627", "version": "v1", "published": "2013-12-19T16:35:41.000Z", "updated": "2013-12-19T16:35:41.000Z", "title": "Duality and syzygies for semimodules over numerical semigroups", "authors": [ "Julio José Moyano-Fernández", "Jan Uliczka" ], "categories": [ "math.CO" ], "abstract": "Let $\\Gamma=\\langle \\alpha, \\beta \\rangle$ be a numerical semigroup. In this article we consider the dual $\\Delta^*$ of a $\\Gamma$-semimodule $\\Delta$; in particular we deduce a formula that expresses the minimal set of generators of $\\Delta^*$ in terms of the generators of $\\Delta$. As applications we compute the minimal graded free resolution of a graded $\\mathbb{F}[t^{\\alpha},t^{\\beta}]$-submodule of $\\mathbb{F}[t]$, and we investigate the structure of the selfdual $\\Gamma$-semimodules, leading to a new way of counting them.", "revisions": [ { "version": "v1", "updated": "2013-12-19T16:35:41.000Z" } ], "analyses": { "subjects": [ "20M14", "05A19" ], "keywords": [ "numerical semigroup", "semimodule", "minimal graded free resolution", "generators", "minimal set" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1312.5627J" } } }