On a number of colors in cyclically interval edgecolorings of trees
Rafayel R. Kamalian · 2010
A proper edge t-coloring of a graph G is a coloring of edges of G with colors 1,2,...,t such that each edge receives one color and no two adjacent edges receive the same color. A proper edge t-coloring of G is called a cyclically interval t-coloring if 1) at least one edge is colored k, for each k=1,2,...,t., and 2) for each vertex v of G the colors of edges incident with v are consecutive modulo t.We find, for an arbitrary tree G, all possible values of t for which G admits a cyclically interval t-coloring.