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arXiv · 1505.06313

Tropical multiplier sequences

Jens Forsgård
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Abstract

We prove that the diagonal operator defined by a positive sequence preserves tropical and central indices if and only if the sequence is log-concave. In particular we obtain an elementary proof of that such an operator preserves the set of sign-independently real-rooted polynomials if and only if the sequence is log-concave.

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Jens Forsgård. 2015-05-23. Tropical multiplier sequences. https://arxiv.org/abs/1505.06313

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