Circular (4 โ \epsilon)-coloring of some classes of signed graphs
Circular (4 โ \epsilon)-coloring of some classes of signed graphs
A circular r-coloring of a signed graph (G, ฯ) is an assignment ฯ of points of a circle C r of circumference r to the vertices of (G, ฯ) such that for each positive edge uv of (G, ฯ) the distance of ฯ(v) and ฯ(v) is at least 1 and โฆ