A Combinatorial Proof of the Log-Concavity of a Famous Sequence Counting Permutations
نویسنده
چکیده
We provide a combinatorial proof for the fact that for any fixed n, the sequence {i(n, k)}0≤k≤(n2) of the numbers of permutations of length n having k inversions is log-concave.
منابع مشابه
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عنوان ژورنال:
- Electr. J. Comb.
دوره 11 شماره
صفحات -
تاریخ انتشار 2005