{ "id": "1702.06519", "version": "v1", "published": "2017-02-21T18:47:35.000Z", "updated": "2017-02-21T18:47:35.000Z", "title": "A New Approach to the $r$-Whitney Numbers by Using Combinatorial Differential Calculus", "authors": [ "José L. Ramírez", "Miguel A. Méndez" ], "categories": [ "math.CO" ], "abstract": "In the present article we introduce two new combinatorial interpretations of the $r$-Whitney numbers of the second kind obtained from the combinatorics of the differential operators associated to the grammar $G:=\\{ y\\rightarrow yx^{m}, x\\rightarrow x\\}$. By specializing $m=1$ we obtain also a new combinatorial interpretation of the $r$-Stirling numbers of the second kind. Again, by specializing to the case $r=0$ we introduce a new generalization of the Stirling number of the second kind and through them a binomial type family of polynomials that generalizes Touchard's. Moreover, we show several well-known identities involving the $r$-Dowling polynomials and the $r$-Whitney numbers using the combinatorial differential calculus. Finally we prove that the $r$-Dowling polynomials are a Sheffer family relative to the generalized Touchard binomial family, study their umbral inverses, and introduce $[m]$-Stirling numbers of the first kind. From the relation between umbral calculus and the Riordan matrices we give several new combinatorial identities involving the $r$-Whitney number of both kinds, Bernoulli and Euler polynomials.", "revisions": [ { "version": "v1", "updated": "2017-02-21T18:47:35.000Z" } ], "analyses": { "subjects": [ "11B83", "11B73", "05A15", "05A19" ], "keywords": [ "combinatorial differential calculus", "whitney number", "second kind", "stirling number", "combinatorial interpretation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }