{ "id": "2401.11245", "version": "v1", "published": "2024-01-20T14:57:15.000Z", "updated": "2024-01-20T14:57:15.000Z", "title": "Construction of the log-convex minorant of a sequence $\\{M_α\\}_{α\\in\\mathbb{N}_0^d}$", "authors": [ "Chiara Boiti", "David Jornet", "Alessandro Oliaro", "Gerhard Schindl" ], "categories": [ "math.FA" ], "abstract": "We give a simple construction of the log-convex minorant of a sequence $\\{M_\\alpha\\}_{\\alpha\\in\\mathbb{N}_0^d}$ and consequently extend to the $d$-dimensional case the well-known formula that relates a log-convex sequence $\\{M_p\\}_{p\\in\\mathbb{N}_0}$ to its associated function $\\omega_M$, that is $M_p=\\sup_{t>0}t^p\\exp(-\\omega_M(t))$. We show that in the more dimensional anisotropic case the classical log-convex condition $M_\\alpha^2\\leq M_{\\alpha-e_j}M_{\\alpha+e_j}$ is not sufficient: convexity as a function of more variables is needed (not only coordinate-wise). We finally obtain some applications to the inclusion of spaces of rapidly decreasing ultradifferentiable functions in the matrix weighted setting.", "revisions": [ { "version": "v1", "updated": "2024-01-20T14:57:15.000Z" } ], "analyses": { "subjects": [ "40B05", "46A13", "46A45" ], "keywords": [ "log-convex minorant", "dimensional anisotropic case", "dimensional case", "well-known formula", "log-convex sequence" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }