Results 61 to 70 of about 4,776 (247)
So-called ordered variants of the classical notions of pathwidth and treewidth are introduced and proposed as proof theoretically meaningful complexity measures for the directed acyclic graphs underlying proofs. Ordered pathwidth is roughly the same as proof space and the ordered treewidth of a proof is meant to serve as a measure of how far it is from
Moritz Müller, Stefan Szeider
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Stable gonality is computable [PDF]
Stable gonality is a multigraph parameter that measures the complexity of a graph. It is defined using maps to trees. Those maps, in some sense, divide the edges equally over the edges of the tree; stable gonality asks for the map with the minimum number
Ragnar Groot Koerkamp +1 more
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Treewidth and Hyperbolicity of the Internet [PDF]
We study the measurement of the Internet according to two graph parameters: treewidth and hyperbolicity. Both tell how far from a tree a graph is. They are computed from snapshots of the Internet released by CAIDA, DIMES, AQUALAB, UCLA, Rocketfuel and Strasbourg University, at the AS or at the router level.
de Montgolfier, Fabien +2 more
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An improved algorithm for the vertex cover $P_3$ problem on graphs of bounded treewidth [PDF]
Given a graph $G=(V,E)$ and a positive integer $t\geq2$, the task in the vertex cover $P_t$ ($VCP_t$) problem is to find a minimum subset of vertices $F\subseteq V$ such that every path of order $t$ in $G$ contains at least one vertex from $F$.
Zongwen Bai, Jianhua Tu, Yongtang Shi
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Treewidth-Aware Cycle Breaking for Algebraic Answer Set Counting
Probabilistic reasoning, parameter learning, and most probable explanation inference for answer set programming have recently received growing attention.
Thomas Eiter +2 more
semanticscholar +1 more source
Tree-width for first order formulae [PDF]
We introduce tree-width for first order formulae \phi, fotw(\phi). We show that computing fotw is fixed-parameter tractable with parameter fotw. Moreover, we show that on classes of formulae of bounded fotw, model checking is fixed parameter tractable ...
Isolde Adler, Mark Weyer
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Optimizing tree decompositions in MSO [PDF]
The classic algorithm of Bodlaender and Kloks [J. Algorithms, 1996] solves the following problem in linear fixed-parameter time: given a tree decomposition of a graph of (possibly suboptimal) width k, compute an optimum-width tree decomposition of the ...
Mikołaj Bojańczyk, Michał Pilipczuk
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The pathwidth and treewidth of cographs [PDF]
Summary: It is shown that the pathwidth of a cograph equals its treewidth, and a linear time algorithm to determine the pathwidth of a cograph and build a corresponding path-decomposition is given.
Hans L. Bodlaender, Rolf H. Möhring
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On the treewidth of Hanoi graphs
The objective of the well-known Towers of Hanoi puzzle is to move a set of disks one at a time from one of a set of pegs to another, while keeping the disks sorted on each peg. We propose an adversarial variation in which the first player forbids a set of states in the puzzle, and the second player must then convert one randomly-selected state to ...
David Eppstein +2 more
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Parameterized Complexity of Equitable Coloring [PDF]
A graph on $n$ vertices is equitably $k$-colorable if it is $k$-colorable and every color is used either $\left\lfloor n/k \right\rfloor$ or $\left\lceil n/k \right\rceil$ times.
Guilherme de C. M. Gomes +2 more
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