On integral sum graphs with a saturated vertex
Czechoslovak Mathematical Journal, Tome 60 (2010) no. 3, pp. 669-674
Cet article a éte moissonné depuis la source Czech Digital Mathematics Library
As introduced by F. Harary in 1994, a graph $ G$ is said to be an $integral$ $ sum$ $ graph$ if its vertices can be given a labeling $f$ with distinct integers so that for any two distinct vertices $u$ and $v$ of $G$, $uv$ is an edge of $G$ if and only if $ f(u)+f(v)=f(w)$ for some vertex $w$ in $G$. \endgraf We prove that every integral sum graph with a saturated vertex, except the complete graph $K_3$, has edge-chromatic number equal to its maximum degree. (A vertex of a graph $G$ is said to be {\it saturated} if it is adjacent to every other vertex of $G$.) Some direct corollaries are also presented.
As introduced by F. Harary in 1994, a graph $ G$ is said to be an $integral$ $ sum$ $ graph$ if its vertices can be given a labeling $f$ with distinct integers so that for any two distinct vertices $u$ and $v$ of $G$, $uv$ is an edge of $G$ if and only if $ f(u)+f(v)=f(w)$ for some vertex $w$ in $G$. \endgraf We prove that every integral sum graph with a saturated vertex, except the complete graph $K_3$, has edge-chromatic number equal to its maximum degree. (A vertex of a graph $G$ is said to be {\it saturated} if it is adjacent to every other vertex of $G$.) Some direct corollaries are also presented.
Classification :
05C15, 05C78
Keywords: integral sum graph; saturated vertex; edge-chromatic number
Keywords: integral sum graph; saturated vertex; edge-chromatic number
@article{CMJ_2010_60_3_a5,
author = {Chen, Zhibo},
title = {On integral sum graphs with a saturated vertex},
journal = {Czechoslovak Mathematical Journal},
pages = {669--674},
year = {2010},
volume = {60},
number = {3},
mrnumber = {2672408},
zbl = {1224.05439},
language = {en},
url = {http://geodesic.mathdoc.fr/item/CMJ_2010_60_3_a5/}
}
Chen, Zhibo. On integral sum graphs with a saturated vertex. Czechoslovak Mathematical Journal, Tome 60 (2010) no. 3, pp. 669-674. http://geodesic.mathdoc.fr/item/CMJ_2010_60_3_a5/