The descent statistic on involutions is not log-concave
نویسندگان
چکیده
We establish a combinatorial connection between the sequence (in,k) counting the involutions on n letters with k descents and the sequence (an,k) enumerating the semistandard Young tableaux on n cells with k symbols. This allows us to show that the sequences (in,k) are not log-concave for some values of n, hence answering a conjecture due to F. Brenti.
منابع مشابه
The descent statistic on involutions is not log -
We establish a combinatorial connection between the sequence (in,k) counting the involutions on n letters with k descents and the sequence (an,k) enumerating the semistandard Young tableaux on n cells with k symbols. This allows us to show that the sequences (in,k) are not log-concave for some values of n, hence answering a conjecture due to F. Brenti.
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عنوان ژورنال:
- Eur. J. Comb.
دوره 30 شماره
صفحات -
تاریخ انتشار 2009