{ "id": "2204.01008", "version": "v1", "published": "2022-04-03T06:50:49.000Z", "updated": "2022-04-03T06:50:49.000Z", "title": "Turán inequalities from Chebyshev to Laguerre polynomials", "authors": [ "Bernhard Heim", "Markus Neuhauser", "Robert Troeger" ], "categories": [ "math.CA", "math.NT" ], "abstract": "Let $g$ and $h$ be real-valued arithmetic functions, positive and normalized. Specific choices within the following general scheme of recursively defined polynomials \\begin{equation*} P_n^{g,h}(x):= \\frac{x}{h(n)} \\sum_{k=1}^{n} g(k) \\, P_{n-k}^{g,h}(x), \\end{equation*} with initial value $P_{0}^{g,h}(x)=1$ encode information about several classical, widely studied polynomials. This includes Chebyshev polynomials of the second kind, associated Laguerre polynomials, and the Nekrasov--Okounkov polynomials. In this paper we prove that for $g(n)=n$ and fixed $h$ we obtain orthogonal polynomial sequences for positive definite functionals. Let $h(n)=n^s$ with $0 \\leq s \\leq 1 $. Then the sequence satisfies Tur\\'an inequalities for $x \\geq 0$.", "revisions": [ { "version": "v1", "updated": "2022-04-03T06:50:49.000Z" } ], "analyses": { "keywords": [ "laguerre polynomials", "turán inequalities", "sequence satisfies turan inequalities", "orthogonal polynomial sequences", "real-valued arithmetic functions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }