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arXiv · 1803.10308

The $1/k$-Eulerian Polynomials as Moments, via Exponential Riordan Arrays

Paul Barry
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Abstract

Using the theory of exponential Riordan arrays, we show that the $1/k$-Eulerian polynomials are moments for a paramaterized family of orthogonal polynomials. In addition, we show that the related Savage-Viswanathan polynomials are also moments for appropriate families of orthogonal polynomials. We provide continued fraction ordinary generating functions and Hankel transforms for these moments, as well as the three-term recurrences for the corresponding orthogonal polynomials. We provide formulas for the $1/k$-Eulerian polynomials and the Savage-Viswanathan polynomials involving the Stirling numbers of the first and the second kind. Finally we show that the once-shifted polynomials are again moment sequences.

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Paul Barry. 2018-03-27. The $1/k$-Eulerian Polynomials as Moments, via Exponential Riordan Arrays. https://arxiv.org/abs/1803.10308

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