TY  - JOUR
ID  - Czap2015
LB  - Czap2015
AU  - Czap, Július
TI  - A note on M<sub>2</sub>-edge colorings of graphs
ST  - A note on M<sub>2</sub>-edge colorings of graphs
JO  - Opuscula Math.
JA  - Opuscula Math.
JF  - Opuscula Mathematica
PY  - 2015
VL  - 35
IS  - 3
SP  - 287
EP  - 291
DO  - http://dx.doi.org/10.7494/OpMath.2015.35.3.287
UR  - http://dx.doi.org/10.7494/OpMath.2015.35.3.287
AB  - An edge coloring \(\varphi\) of a graph \(G\) is called an \(M_2\)-edge coloring if \(|\varphi(v)|\le2 \) for every vertex \(v\) of \(G\), where \(\varphi(v)\) is the set of colors of edges incident with \(v\). Let \(K_2(G)\) denote the maximum number of colors used in an \(M_2\)-edge coloring of \(G\). Let \(G_1\), \(G_2\) and \(G_3\) be graphs such that \(G_1\subseteq G_2\subseteq G_3\). In this paper we deal with the following question: Assuming that \(K_2(G_1)=K_2(G_3)\), does it hold \(K_2(G_1)=K_2(G_2)=K_2(G_3)\)?
KW  - edge coloring
KW  - graph
SN  - 1232-9274
ER  -