Results 21 to 30 of about 147,262 (199)
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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Enumerative Combinatorics of Lattice Polymers
, 2021 DOI: https://doi.org/10.1090/noti2255 physicists who appreciatemathematical beauty), the physicallymotivatedmodels aremathematically appealing, and have rich combinatorial structure. The third reason is that it is just a really fun research topic.
N. Clisby
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Note on r-central Lah numbers and r-central Lah-Bell numbers
AIMS Mathematics, 2022 The r-Lah numbers generalize the Lah numbers to the r-Stirling numbers in the same sense. The Stirling numbers and the central factorial numbers are one of the important tools in enumerative combinatorics. The r-Lah number counts the number of partitions
Hye Kyung Kim
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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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Enumerative Combinatorics of Intervals in the Dyck Pattern Poset [PDF]
Order, 2019 We initiate the study of the enumerative combinatorics of the intervals in the Dyck pattern poset. More specifically, we find some closed formulas to express the size of some specific intervals, as well as the number of their covering relations.
A. Bernini +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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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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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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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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