We study the properties of a logconcavity operator on a symmetric, unimodal
subset of finite sequences. In doing so we are able to prove that there is a
large unbounded region in this subset that is ∞-logconcave. This problem
was motivated by the conjecture of Moll and Boros in that the binomial
coefficients are ∞-logconcave.Comment: 12 pages, final version incorporating referee's comments. Now
published by the Electronic Journal of Combinatorics
http://www.combinatorics.org/index.htm