Results 1 to 10 of about 11,738 (234)
Congruence for Lattice Path Models with Filter Restrictions and Long Steps
Mathematics, 2022 We derive a path counting formula for a two-dimensional lattice path model with filter restrictions in the presence of long steps, source and target points of which are situated near the filters. This solves the problem of finding an explicit formula for
Dmitry Solovyev
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Polyominoes determined by involutions [PDF]
Discrete Mathematics & Theoretical Computer Science, 2008 A permutomino of size n is a polyomino determined by particular pairs $(\pi_1, \pi_2)$ of permutations of length $n$, such that $\pi_1(i) \neq \pi_2(i)$, for $1 \leq i \leq n$.
Filippo Disanto, Simone Rinaldi
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PreLie-decorated hypertrees [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 Weighted hypertrees have been used by C. Jensen, J. McCammond, and J. Meier to compute some Euler characteristics in group theory. We link them to decorated hypertrees and 2-coloured rooted trees. After the enumeration of pointed and non-pointed types of
Bérénice Oger
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Generation modulo the action of a permutation group [PDF]
Discrete Mathematics & Theoretical Computer Science, 2013 Originally motivated by algebraic invariant theory, we present an algorithm to enumerate integer vectors modulo the action of a permutation group. This problem generalizes the generation of unlabeled graph up to an isomorphism.
Nicolas Borie
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Transactions of the Karelian Research Centre of the Russian Academy of Sciences, 2019 The scheme of allocating r distinguishable particles into n indistinguishable cells with k non-empty cells is studied along the directions of enumerative combinatorics.
Natalia Enatskaya
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Discrete Mathematics & Theoretical Computer Science, 2014 A general lattice theoretic construction of Reading constructs Hopf subalgebras of the Malvenuto-Reutenauer Hopf algebra (MR) of permutations. The products and coproducts of these Hopf subalgebras are defined extrinsically in terms of the embedding in MR.
Shirley Law
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Generalized triangulations, pipe dreams, and simplicial spheres [PDF]
Discrete Mathematics & Theoretical Computer Science, 2011 We exhibit a canonical connection between maximal $(0,1)$-fillings of a moon polyomino avoiding north-east chains of a given length and reduced pipe dreams of a certain permutation.
Luis Serrano, Christian Stump
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Many 2-level polytopes from matroids [PDF]
, 2015 The family of 2-level matroids, that is, matroids whose base polytope is 2-level, has been recently studied and characterized by means of combinatorial properties.
Grande, Francesco, Rué, Juanjo
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Combinatorics of Second Derivative: Graphical Proof of Glaisher-Crofton Identity
Advances in Mathematical Physics, 2018 We give a purely combinatorial proof of the Glaisher-Crofton identity which is derived from the analysis of discrete structures generated by the iterated action of the second derivative.
Pawel Blasiak +2 more
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Fourier series of functions involving higher-order ordered Bell polynomials
Open Mathematics, 2017 In 1859, Cayley introduced the ordered Bell numbers which have been used in many problems in number theory and enumerative combinatorics. The ordered Bell polynomials were defined as a natural companion to the ordered Bell numbers (also known as the ...
Kim Taekyun +3 more
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