Results 21 to 24 of about 165 (24)

Web matrices : structural properties and generating combinatorial identities [PDF]

, 2016
In this paper we present new results for the combinatorics of web diagrams and web worlds. These are discrete objects that arise in the physics of calculating scattering amplitudes in non-abelian gauge theories.
Dukes, Mark, White, Chris D.
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and [PDF]

. We study the descent distribution over the set of centrosymmetric permutations that avoid a pattern of length 3. In the most puzzling case, namely, τ = 123 and n even, our main tool is a bijection that associates a Dyck pre x of length 2n to every ...
Flavio Bonetti, Marilena Barnabei, Matteo Silimbani   +2 more
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The Eulerian numbers on restricted centrosymmetric permutations

, 2009
We study the descent distribution over the set of centrosymmetric permutations that avoid the pattern of length 3. Our main tool in the most puzzling case, namely, $\tau=123$ and $n$ even, is a bijection that associates a Dyck prefix of length $2n$ to ...
Barnabei, Marilena, Bonetti, Flavio, Silimbani, Matteo   +2 more
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Set-Valued Tableaux & Generalized Catalan Numbers

, 2017
Standard set-valued Young tableaux are a generalization of standard Young tableaux in which cells may contain more than one integer, with the added conditions that every integer at position $(i,j)$ must be smaller than every integer at positions $(i,j+1)$
Drube, Paul
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