41–60 of
129 results.

Vladimir R. Rosenfeld
A {\em retractingfree bidirectional circuit} in a graph $G$ is a closed walk which traverses every edge exactly once in each direction and such that no edge is succeeded by the same edge in the oppos...

Anie Lusiani
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Edy Tri Baskoro
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Suhadi Wido Saputro
Let $K_{l\times t}$ be a complete, balanced, multipartite graph consisting of $l$ partite sets and $t$ vertices in each partite set. For given two graphs $G_1$ and $G_2$, and integer $j\geq 2$, the si...

Alain Valette
For a finite connected graph $X$, we consider the graph $RX$ obtained from $X$ by associating a new vertex to every edge of $X$ and joining by edges the extremities of each edge of $X$ to the correspo...

Padmapriya P.
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Veena Mathad
Let $G = (V,E)$ be a simple connected graph. Theeccentricdistance sum of $G$ is defined as$\xi^{ds}(G) =\ds\sum_{\{u,v\}\subseteq V(G)} [e(u)+e(v)] d(u,v)$, where $e(u)$ %\dsis the eccentricity of th...

K. Pravas
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A. Vijayakumar
The Gallai and the antiGallai graphs of a graph $G$ are complementary pairs of spanning subgraphs of the line graph of $G$. In this paper we find some structural relations between these graph classes...

Thodoris Karatasos
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Evi Papaioannou
In this work, we present an innovative image recognition technique which is based on the exploitation of transitdata in images or simple photographs of sites of interest. Our objective is to automati...

I. Nengah Suparta
A Gray code of length n is a list of all binary words of length n such that each two successive codewords differ in only one bit position. If the first and the last codewords also share this property,...

V. Yegnanarayanan
Let $p \ge 3$ be a positive integer and let $k \in {1, 2, ..., p1} \ \lfloor p/2 \rfloor$. The generalized Petersen graph GP(p,k) has its vertex and edge set as $V(GP(p, k)) = \{u_i : i \in Zp\} \cup...

Kijung Kim
In 2010, Kim, Park and Sano studied the competition numbers of Johnson graphs. They gave the competition numbers of J(n,2) and J(n,3).In this note, we consider the competition number of J(n,4).

Faraha Ashraf
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Martin Baca
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Andrea SemanicovaFenovcikova
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Ayesha Shabbir
A simple graph G=(V(G),E(G)) admits an Hcovering if every edge in E(G) belongs at least to one subgraph of G isomorphic to a given graph H. Then the graph G admitting Hcovering admits an Hirregular...

Suk J. Seo
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Peter J. Slater
A distinguishing set for a graph G = (V, E) is a dominating set D, each vertex $v \in D$ being the location of some form of a locating device, from which one can detect and precisely identify any give...

Steven Schluchter
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J. Z. Schroeder
A proper embedding of a graph G in a pseudosurface P is an embedding in which the regions of the complement of G in P are homeomorphic to discs and a vertex of G appears at each pinchpoint in P; we s...

Mustapha Aouchiche
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Pierre Hansen
The paper discusses bounds on the nullity number of graphs. It is proved in [B. Cheng and B. Liu, On the nullity of graphs. Electron. J. Linear Algebra 16 (2007) 6067] that $\eta \le n  D$, where $...

Mehdi Alaeiyan
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Ayoob Mehrabani
Perfect coloring is a generalization of the notion of completely regular codes, given by Delsarte. A perfect mcoloring of a graph G with m colors is a partition of the vertex set of G into m parts A_...

RadosÅ‚aw Cymer
In decomposition theory, extreme sets have been studied extensively due to its connection to perfect matchings in a graph. In this paper, we first define extreme sets with respect to degreematchings ...

Amrita Acharyya
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Jon M. Corson
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Bikash Das
We generalize the idea of cofinite groups, due to B. Hartley, [2]. First we define cofinite spaces in general. Then, as a special situation, we study cofinite graphs and their uniform completions.The ...

Hamed Ghasemian Zoeram
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Daniel Yaqubi
A vertex of degree one is called an endvertex and the set of endvertices of G is denoted by End(G). For a positive integer k, a tree T be called kended tree if $End(T) \leq k$. In this paper, we ...

Kamal Lochan Patra
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Binod Kumar Sahoo
This paper is a survey on the upper and lower bounds for the largest eigenvalue of the Laplacian matrix, known as the Laplacian spectral radius, of a graph. The bounds are given as functions of graph ...

Anak Agung Gede Ngurah
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Rinovia Simanjuntak
A graph G of order p and size q is called super edgemagic if there exists a bijective function f from V(G) U E(G) to {1, 2, 3, ..., p+q} such that f(x) + f(xy) + f(y) is a constant for every edge $xy...

Bryan Freyberg
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Melissa Keranen
The following generalization of distance magic graphs was introduced in [2]. A directed Z_ndistance magic labeling of an oriented graph $\overrightarrow{G}=(V,A)$ of order n is a bijection $\overrigh...