Results 241 to 247 of about 63,637 (247)

An interchange property for the rooted phylogenetic subnet diversity on phylogenetic networks. [PDF]

J Math Biol
Coronado TM, Riera G, Rosselló F.
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Forbidden Induced Subgraphs for Toughness

Journal of Graph Theory, 2012
Let be a family of connected graphs. A graph G is said to be -free if G is H-free for every graph H in . We study the relation between forbidden subgraphs in a connected graph G and the resulting toughness of G. In particular, we consider the problem of characterizing the graph families such that every large enough connected -free graph is t-tough.
Katsuhiro Ota, Gabriel Sueiro
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On induced subgraphs of a block

Journal of Graph Theory, 1977
AbstractIf G is a block, then a vertex u of G is called critical if G ‐ u is not a block. In this article, relationships between the localization of critical vertices and the localization of vertices of relatively small degrees (especially, of degree two) are studied. A block is called semicritical if a) each edge is incident with at least one critical
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Excluding induced subgraphs

2007
In this paper we survey some results concerning the structure and properties of families of graphs defined by excluding certain induced subgraphs, including perfect graphs, claw-free graphs, even-hole-free graphs and others.
Paul Seymour, Maria Chudnovsky
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Cuts and Induced Bipartite Subgraphs

2017
In this chapter we compare three popular models for the maximum cut problem and show the equivalence of their relaxations by using compact extended formulations. These problems are closely related to the subject of edge-induced and node-induced bipartite subgraphs, for which we give compact extended formulations as well.
Lancia G., Serafini P.
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Excluding induced subgraphs: quadrilaterals

Random Structures & Algorithms, 1991
AbstractIn this note we determine the structure of “almost all” graphs not containing a quadrilateral (i.e., a cycle of length four) as an induced subgraph. In particular, it turns out that there are asymptotically twice as many graphs not containing an induced quadrilateral than there are bipartite graphs.
Angelika Steger, Hans Jürgen Prömel
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Induced Subgraphs in a Random Graph

1987
For a class of sequences (F k ) of graphs with v k vertices and e k edges, k=1, 2, …, we show that the size T n of largest induced copy of a graph from {F 1 , F 2 , …} in a random graph K(n,p) divided by log n tends to 2/ A, as n→θ, with probability 1, where A = a log 1/p + (1-a) log 1/(1-p) and .
Andrzej Ruciński, Andrzej Ruciński
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