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arXiv · 0901.1379

Pseudo-factorials, elliptic functions, and continued fractions

Roland Bacher·Philippe Flajolet
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Abstract

This study presents miscellaneous properties of pseudo-factorials, which are numbers whose recurrence relation is a twisted form of that of usual factorials. These numbers are associated with special elliptic functions, most notably, a Dixonian and a Weierstrass function, which parametrize the Fermat cubic curve and are relative to a hexagonal lattice. A continued fraction expansion of the ordinary generating function of pseudo-factorials, first discovered empirically, is established here. This article also provides a characterization of the associated orthogonal polynomials, which appear to form a new family of "elliptic polynomials", as well as various other properties of pseudo-factorials, including a hexagonal lattice sum expression and elementary congruences.

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Roland Bacher, Philippe Flajolet. 2009-05-31. Pseudo-factorials, elliptic functions, and continued fractions. https://arxiv.org/abs/0901.1379

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