Results 1 to 10 of about 342 (139)
THE (△,□)-EDGE GRAPH G△,□ OF A GRAPH G [PDF]
Journal of Algebraic Systems, 2020 To a simple graph $G=(V,E)$, we correspond a simple graph $G_{\triangle,\square}$ whose vertex set is $\{\{x,y\}: x,y\in V\}$ and two vertices $\{x,y\},\{z,w\}\in G_{\triangle,\square}$ are adjacent if and only if $\{x,z\},\{x,w\},\{y,z\},\{y,w\}\in V ...
Gh. A. Nasiriboroujeni +2 more
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Enumeration of Graded (3 + 1)-Avoiding Posets [PDF]
Discrete Mathematics & Theoretical Computer Science, 2012 The notion of (3+1)-avoidance appears in many places in enumerative combinatorics, but the natural goal of enumerating all (3+1)-avoiding posets remains open. In this paper, we enumerate \emphgraded (3+1)-avoiding posets.
Joel Lewis Brewster, Yan X Zhang
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Applications in Enumerative Combinatorics of In finite Weighted Automata and Graphs [PDF]
Scientific Annals of Computer Science, 2014 In this paper, we present a general methodology to solve a wide variety of classical lattice path counting problems in a uniform way. These counting problems are related to Dyck paths, Motzkin paths and some generalizations. The methodology uses weighted
R. De Castro, A. Ramírez, J.L. Ramírez
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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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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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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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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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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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