Results 221 to 230 of about 2,976 (243)

On Factorable Extensions and Subgraphs of Prime Graphs

SIAM Journal on Discrete Mathematics, 1989
Summary: Cartesian-factorable extensions and subgraphs of prime graphs are investigated. It is shown that minimal factorable extensions and maximal factorable subgraphs are not unique and that finding them is NP-hard even, in the case of minimal factorable extensions, if the prime graph in question is required to be a tree.
Joan Feigenbaum, Ramsey W. Haddad
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On Prime Distance Labeling of Graphs

2017
A graph G is a prime distance graph if its vertices can be labeled with distinct integers in such a way that for any two adjacent vertices, the absolute difference of their labels is a prime number. It is known that cycles and bipartite graphs are prime distance graphs. In this paper we derive certain general results concerning prime distance labeling.
A. Parthiban, N. Gnanamalar David
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Reducing prime graphs and recognizing circle graphs

Combinatorica, 1987
A reduction theorem for prime (simple) graphs in \textit{W. H. Cunningham}'s sense [SIAM J. Algebraic Discrete Methods 3, 214-228 (1982; Zbl 0497.05031)] is presented. It says that every prime graph of order \(n>5\) contains a smaller prime graph of order n-1.
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Vertex‐transitive graphs: Symmetric graphs of prime valency

Journal of Graph Theory, 1984
AbstractLet G be a group acting symmetrically on a graph Σ, let G1 be a subgroup of G minimal among those that act symmetrically on Σ, and let G2 be a subgroup of G1 maximal among those normal subgroups of G1 which contain no member except 1 which fixes a vertex of Σ. The most precise result of this paper is that if Σ has prime valency p, then either Σ
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Prime Testing for the Split Decomposition of a Graph

SIAM Journal on Discrete Mathematics, 1989
Summary: An \(O(n^ 2)\) algorithm for testing whether a graph is decomposable with respect to the split decomposition is developed. The fastest previous algorithm required \(\Omega (n^ 3)\) time for this problem. This leads to an \(O(n^ 2)\) expected time algorithm for computing the split decomposition of a graph.
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Prime Graphs of Some Graphs

Journal of Advanced Research in Dynamical and Control Systems, 2020
Simaringa M, Santhoshkumar K
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Cocliques of maximal size in the prime graph of a finite simple group

Algebra and Logic, 2011
A V Vasil´Ev, E P Vdovin, Vasil'Ev A V
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Recognition of finite groups by the prime graph

Algebra and Logic, 2006
Andrei V Zavarnitsine, Zavarnitsine A V
exaly  

On the prime graph of PSL(2, p) where p > 3 is a prime number

Acta Mathematica Hungarica, 2007
Bahman Khosravi, Behnam Khosravi, Behrooz Khosravi   +2 more
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An Adjacency Criterion for the Prime Graph of a Finite Simple Group

Algebra and Logic, 2005
E P Vdovin, Vdovin E P
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