Power series with positive coefficients arising from the characteristic polynomials of positive matrices

Thomas J. Laffey; Raphael Loewy; Helena Šmigoc

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arXiv · 1205.1933

Power series with positive coefficients arising from the characteristic polynomials of positive matrices

Thomas J. Laffey·Raphael Loewy·Helena Šmigoc

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Abstract

Let A be an nxn (entrywise) positive matrix and let f(t)=det(I-t A). We prove that there always exists a positive integer N such that 1-f(t)^{1/N} has positive coefficients.

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Thomas J. Laffey, Raphael Loewy, Helena Šmigoc. 2013-07-17. Power series with positive coefficients arising from the characteristic polynomials of positive matrices. https://arxiv.org/abs/1205.1933

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