Results 21 to 30 of about 35,860 (197)
Total positivity for cominuscule Grassmannians [PDF]
Discrete Mathematics & Theoretical Computer Science, 2008 In this paper we explore the combinatorics of the non-negative part $(G/P)_{\geq 0}$ of a cominuscule Grassmannian. For each such Grassmannian we define Le-diagrams ― certain fillings of generalized Young diagrams which are in bijection with the cells of
Thomas Lam, Lauren Williams
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New directions in enumerative chess problems [PDF]
, 2005 Normally a chess problem must have a unique solution, and is deemed unsound even if there are alternatives that differ only in the order in which the same moves are played.
Elkies, Noam
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Urn Sampling Without Replacement: Enumerative Combinatorics in R
Journal of Statistical Software, 2007 This short paper introduces a code snippet in the form of two new R functions that enumerate possible draws from an urn without replacement; these functions call C code, written by the author.
Robin K. S. Hankin
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A Didactic Analysis of Functional Queues
Informatics in Education, 2011 When first introduced to the analysis of algorithms, students are taught how to assess the best and worst cases, whereas the mean and amortized costs are considered advanced topics, usually saved for graduates.
Christian RINDERKNECHT
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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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Well quasi-order in combinatorics : embeddings and homomorphisms [PDF]
, 2015 The notion of well quasi-order (wqo) from the theory of ordered sets often arises naturally in contexts where one deals with infinite collections of structures which can somehow be compared, and it then represents a useful discriminator between ‘tame ...
Ruskuc, Nik +3 more
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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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