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Clique-Relaxed Graph Coloring [PDF]
We define a generalization of the chromatic number of a graph G called the k-clique-relaxed chromatic number, denoted χ(k)(G). We prove bounds on χ(k)(G) for all graphs G, including corollaries for outerplanar and planar graphs.
Dunn, Charles+5 more
core +2 more sources
Alpha Labeling of Amalgamated Cycles
A graceful labeling of a bipartite graph is an \a-labeling if it has the property that the labels assigned to the vertices of one stable set of the graph are smaller than the labels assigned to the vertices of the other stable set.
Christian Barrientos
doaj +1 more source
Star edge coloring of $ K_{2, t} $-free planar graphs
The star chromatic index of a graph $ G $, denoted by $ \chi{'}_{st}(G) $, is the smallest number of colors required to properly color $ E(G) $ such that every connected bicolored subgraph is a path with no more than three edges.
Yunfeng Tang , Huixin Yin , Miaomiao Han
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Every Property of Outerplanar Graphs is Testable [PDF]
A D-disc around a vertex v of a graph G=(V,E) is the subgraph induced by all vertices of distance at most D from v. We show that the structure of an outerplanar graph on n vertices is determined, up to modification (insertion or deletion) of at most ...
Babu, Jasine+2 more
core +1 more source
On the Planarity of Generalized Line Graphs
One of the most familiar derived graphs is the line graph. The line graph $L(G)$ of a graph $G$ is that graph whose vertices are the edges of $G$ where two vertices of $L(G)$ are adjacent if the corresponding edges are adjacent in~$G$.
Khawlah H. Alhulwah+2 more
doaj +1 more source
On Supergraphs Satisfying CMSO Properties [PDF]
Let CMSO denote the counting monadic second order logic of graphs. We give a constructive proof that for some computable function $f$, there is an algorithm $\mathfrak{A}$ that takes as input a CMSO sentence $\varphi$, a positive integer $t$, and a ...
Mateus de Oliveira Oliveira
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On Another Class of Strongly Perfect Graphs
For a commutative ring R with unity, the associate ring graph, denoted by AG(R), is a simple graph with vertices as nonzero elements of R and two distinct vertices are adjacent if they are associates.
Neha Kansal+3 more
doaj +1 more source
The Degree-Diameter Problem for Outerplanar Graphs
For positive integers Δ and D we define nΔ,D to be the largest number of vertices in an outerplanar graph of given maximum degree Δ and diameter D. We prove that nΔ,D=ΔD2+O (ΔD2−1)$n_{\Delta ,D} = \Delta ^{{D \over 2}} + O\left( {\Delta ^{{D \over 2 ...
Dankelmann Peter+2 more
doaj +1 more source
Space-Efficient Biconnected Components and Recognition of Outerplanar Graphs [PDF]
We present space-efficient algorithms for computing cut vertices in a given graph with $n$ vertices and $m$ edges in linear time using $O(n+\min\{m,n\log \log n\})$ bits.
Kammer, Frank+2 more
core +2 more sources
Characterization of outerplanar graphs with equal 2-domination and domination numbers
A {\em $k$-domination number} of a graph $G$ is minimum cardinality of a $k$-dominating set of $G$, where a subset $S \subseteq V(G)$ is a {\em $k$-dominating set} if each vertex $v\in V(G)\setminus S$ is adjacent to at least $k$ vertices in $S$.
Naoki Matsumoto
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