All graphs under consideration are nonnull, finite, undirected, and simple graphs. We adopt the standard notations dG(v) for the degree of the vertex v in the graph G, and ∆(G) for the maximum degree of the vertices of G. The edge chromatic number, χ′(G), of G is the minimum number of colors required to color the edges of G in such a way that no two adjacent edges have the same color. A graph i...

A notion of graph-wreath product of groups is introduced. We obtain sufficient conditions for these products to satisfy the topologically inspired finiteness condition type Fn. Under various additional assumptions we show that these conditions are necessary. Our results generalize results of Bartholdi, Cornulier and Kochloukova about wreath products. Graphwreath products of groups include class...

An outer-connected dominating set for an arbitrary graph G is a set D̃ ⊆ V such that D̃ is a dominating set and the induced subgraph G[V \ D̃] be connected. In this paper, we focus on the outerconnected domination number of the product of graphs. We investigate the existence of outer-connected dominating set in lexicographic product and Corona of two arbitrary graphs, and we present upper bounds f...

An interval t coloring of a graph is a proper edgecoloring of with colors 1, such that at least one edge of G is colored by and the edges incident to each vertex − G G 2, , t ... , 1, 2, , , i i t = ... ( ) v V G ∈ are colored by consecutive colors, where is the degree of the vertex in . In this paper interval edge-colorings of various graph products are investigated. ( ) G d v ( ) G d v v G

In this paper, we generalise Magnus’ Freiheitssatz and solution to the word problem for one-relator groups by considering one relator quotients of certain classes of right-angled Artin groups and graph products of locally indicable polycyclic groups.

A graph G is said to be 1-perfectly orientable (1-p.o. for short) if it admits an orientation such that the out-neighborhood of every vertex is a clique in G. The class of 1-p.o. graphs forms a common generalization of the classes of chordal and circular arc graphs. Even though 1-p.o. graphs can be recognized in polynomial time, no structural characterization of 1-p.o. graphs is known. In this ...