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On linear transformations preserving the Pólya Frequency property

Petter Brändén
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Abstract

We prove that certain linear operators preserve the Pólya frequency property and real-rootedness, and apply our results to settle some conjectures and open problems in combinatorics proposed by Bóna, Brenti and Reiner-Welker.

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Petter Brändén. 2004-09-29. On linear transformations preserving the Pólya Frequency property. https://arxiv.org/abs/math/0403364

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