RISC RISC Research Institute for Symbolic Computation  

RISC Talk Announcement

Speaker: Dominique Foata, Strasbourg
Title: Entringer numbers and Poupard Calculus
Date: 13.11. 2013   14:00--15:30
Location: RISC Seminar room pond
Abstract: Refinements of the celebrated tangent and secant numbers give rise to bivariate statistical distributions that can be expressed, either by a finite difference equation system, or by a three-variate exponential generating function. The underlying combinatorial sets, counted by tangent and secant numbers, are the alternating permutations, or the André permutations of the two kinds, or still the binary increasing trees. Emphasis will be made on the calculation of the involved series.
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