Planarity of joined graphs
T. Sitthiwiratham, Chanon Promsakon · Journal of Discrete Mathematical Sciences and Cryptography · 2009
Let G 1 and G 2 be any two graphs. The joined graph of G 1 and G 2, denoted by G 1 V G 2, is the graph that V(G 1 ⋁ G 2) = V(G 1) ∪ V(G 2) and E(G 1 ⋁ G 2) = E(G 1) ∪ E(G 2) ∪ {uv : u ∈ V(G 1), v ∈ V(G 2)}. In this paper, we give graphs that their joined graphs are planar.