Results 31 to 40 of about 312 (179)

Some Characterizations and NP-Complete Problems for Power Cordial Graphs

Journal of Mathematics, 2023
A power cordial labeling of a graph G=VG,EG is a bijection f:VG⟶1,2,…,VG such that an edge e=uv is assigned the label 1 if fu=fvn or fv=fun, for some n∈N∪0 and the label 0 otherwise, and satisfy the number of edges labeled with 0 and the number of edges ...
C. M. Barasara, Y. B. Thakkar
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On Critical Unicyclic Graphs with Cutwidth Four

AppliedMath, 2022
The cutwidth minimization problem consists of finding an arrangement of the vertices of a graph G on a line Pn with n=|V(G)| vertices in such a way that the maximum number of overlapping edges (i.e., the congestion) is minimized.
Zhenkun Zhang, Hongjian Lai
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Coloring Graphs Characterized by a Forbidden Subgraph [PDF]

Discrete Applied Mathematics, 2012
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Golovach, P.A., Paulusma, D., Ries, B.
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Forbidden triples for $2$-connected graphs with minimum degree three which contain $K_4$ and $K_{2,2}$

Theory and Applications of Graphs
For a family $\mathcal{H}$ of graphs, a graph $G$ is said to be $\mathcal{H}$-free if $G$ contains no member of $\mathcal{H}$ as an induced subgraph. Let $\mathcal{G}_2^{(3)}}(\mathcal{H})$ denote the family of $2$-connected $\mathcal{H}$-free graphs ...
Takafumi Kotani, Yoshimi Egawa
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Some new upper bounds of

AKCE International Journal of Graphs and Combinatorics, 2017
The extremal number or simply denotes the maximal number of edges in a graph on vertices with forbidden subgraphs and . The exact number of is only known for up to and . There are upper and lower bounds of for other values of .
Novi H. Bong
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On the chromatic number of (P_{5},windmill)-free graphs [PDF]

Opuscula Mathematica, 2017
In this paper we study the chromatic number of \((P_5, windmill)\)-free graphs. For integers \(r,p\geq 2\) the windmill graph \(W_{r+1}^p=K_1 \vee pK_r\) is the graph obtained by joining a single vertex (the center) to the vertices of \(p\) disjoint ...
Ingo Schiermeyer
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Heavy subgraph pairs for traceability of block-chains

Discussiones Mathematicae Graph Theory, 2014
A graph is called traceable if it contains a Hamilton path, i.e., a path containing all its vertices. Let G be a graph on n vertices. We say that an induced subgraph of G is o−1-heavy if it contains two nonadjacent vertices which satisfy an Ore-type ...
Li Binlong, Broersma Hajo, Zhang Shenggui   +2 more
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A Quasi-Hole Detection Algorithm for Recognizing k-Distance-Hereditary Graphs, with k < 2

Algorithms, 2021
Cicerone and Di Stefano defined and studied the class of k-distance-hereditary graphs, i.e., graphs where the distance in each connected induced subgraph is at most k times the distance in the whole graph. The defined graphs represent a generalization of
Serafino Cicerone
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Graphs with forbidden subgraphs

Journal of Combinatorial Theory, Series B, 1971
AbstractMany graphs which are encountered in the study of graph theory are characterized by a type of configuration or subgraph they possess. However, there are occasions when such graphs are more easily defined or described by the kind of subgraphs they are not permitted to contain.
Chartrand, Gary, Geller, Dennis, Hedetniemi, Stephen   +2 more
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On Sequential Heuristic Methods for the Maximum Independent Set Problem

Discussiones Mathematicae Graph Theory, 2017
We consider sequential heuristics methods for the Maximum Independent Set (MIS) problem. Three classical algorithms, VO [11], MIN [12], or MAX [6] , are revisited. We combine Algorithm MIN with the α-redundant vertex technique[3].
Lê Ngoc C., Brause Christoph, Schiermeyer Ingo   +2 more
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