Results 21 to 30 of about 1,141 (244)
On the enumeration of column-convex permutominoes [PDF]
We study the enumeration of \emphcolumn-convex permutominoes, i.e. column-convex polyominoes defined by a pair of permutations. We provide a direct recursive construction for the column-convex permutominoes of a given size, based on the application of ...
Nicholas R. Beaton +3 more
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Probabilistic models for the analysis of inverse extremal problems in combinatorics [PDF]
In an inverse extremal problem for a combinatorial scheme with a given value of the objective function of the form of a certain extreme value of its characteristic, a probabilistic model is developed that ensures that this value is obtained in its ...
Nataliya Yu. Enatskaya
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The number of planar graphs and properties of random planar graphs [PDF]
We show an asymptotic estimate for the number of labelled planar graphs on $n$ vertices. We also find limit laws for the number of edges, the number of connected components, and other parameters in random planar graphs.
Omer Gimenez, Marc Noy
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On trees, tanglegrams, and tangled chains [PDF]
Tanglegrams are a class of graphs arising in computer science and in biological research on cospeciation and coevolution. They are formed by identifying the leaves of two rooted binary trees. The embedding of the trees in the plane is irrelevant for this
Sara Billey +2 more
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Globalization of the analysis of particle placement models by cells [PDF]
The title of the paper means that its goal is a general approach to the pre-asmptotic analysis of schemes with different qualities in all combinations of their distinguishability of their constituent elements (cells and particles).
Nataliya Yu. Enatskaya
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On the number of series parallel and outerplanar graphs [PDF]
We show that the number $g_n$ of labelled series-parallel graphs on $n$ vertices is asymptotically $g_n \sim g \cdot n^{-5/2} \gamma^n n!$, where $\gamma$ and $g$ are explicit computable constants.
Manuel Bodirsky +3 more
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Mixed Powers of Generating Functions [PDF]
Given an integer $m \geq 1$, let $\| \cdot \|$ be a norm in $\mathbb{R}^{m+1}$ and let $\mathbb{S}_+^m$ denote the set of points $\mathbf{d}=(d_0,\ldots,d_m)$ in $\mathbb{R}^{m+1}$ with nonnegative coordinates and such that $\| \mathbf{d} \|=1$. Consider
Manuel Lladser
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ASYMPTOTIC DENSITY AND COMPUTABLY ENUMERABLE SETS [PDF]
We study connections between classical asymptotic density, computability and computable enumerability. In an earlier paper, the second two authors proved that there is a computably enumerable set A of density 1 with no computable subset of density 1.
Rodney G. Downey +2 more
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Asymptotic Enumeration of RNA Structures with Pseudoknots [PDF]
In this paper we present the asymptotic enumeration of RNA structures with pseudoknots. We develop a general framework for the computation of exponential growth rate and the sub exponential factors for $k$-noncrossing RNA structures. Our results are based on the generating function for the number of $k$-noncrossing RNA pseudoknot structures, ${\sf S}_k(
Jin, Emma Y., Reidys, Christian M.
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Spanning forests in regular planar maps (conference version) [PDF]
We address the enumeration of $p$-valent planar maps equipped with a spanning forest, with a weight $z$ per face and a weight $u$ per component of the forest.
Mireille Bousquet-Mélou +1 more
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