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arXiv · 1211.5496

Infinite Log-Concavity and r-Factor

Zahid Raza·Anjum Iqbal
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Abstract

D. Uminsky and K. Yeats [6] studied the properties of the log- operator L on the subset of the finite symmetric sequences and prove the existence of an infinite region R, bounded by parametrically de- fined hypersurfaces such that any sequence corresponding a point of R is infinitely log concave. We study the properties of a new operator L_r and redefine the hypersurfaces which generalizes the one defined by Uminsky and Yeats [6]. We show that any sequence corresponding a point of the region R, bounded by the new generalized parametrically defined r-factor hypersurfaces, is Generalized r-factor infinitely log concave. We also give an improved value of r_0 found by McNamara and Sagan [4] as the log-concavity criterion using the new log-operator.

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Zahid Raza, Anjum Iqbal. 2012-11-23. Infinite Log-Concavity and r-Factor. https://arxiv.org/abs/1211.5496

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