Two Descent Statistics over 321-Avoiding Centrosymmetric Involutions
نویسندگان
چکیده
منابع مشابه
Two Descent Statistics over 321-Avoiding Centrosymmetric Involutions
Centrosymmetric involutions in the symmetric group S2n are permutations π such that π = π−1 and π(i) + π(2n + 1 − i) = 2n + 1 for all i, and they are in bijection with involutions of the hyperoctahedral group. We describe the distribution of some natural descent statistics on 321-avoiding centrosymmetric involutions, including the number of descents in the first half of the involution, and the ...
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Centrosymmetric involutions in the symmetric group S2n are permutations π such that π = π−1 and π(i) + π(2n+1− i) = 2n+1 for all i, and they are in bijection with involutions of the hyperoctahedral group. We describe the distribution of some natural descent statistics on 321-avoiding centrosymmetric involutions, including the number of descents in the first half of the involution, and the sum o...
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ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2016
ISSN: 1077-8926
DOI: 10.37236/5531