On Unimodality Problems in Pascal's Triangle

نویسندگان

  • Xun-Tuan Su
  • Yi Wang
چکیده

Many sequences of binomial coefficients share various unimodality properties. In this paper we consider the unimodality problem of a sequence of binomial coefficients located in a ray or a transversal of the Pascal triangle. Our results give in particular an affirmative answer to a conjecture of Belbachir et al which asserts that such a sequence of binomial coefficients must be unimodal. We also propose two more general conjectures.

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عنوان ژورنال:
  • Electr. J. Comb.

دوره 15  شماره 

صفحات  -

تاریخ انتشار 2008