Radio mean labeling of a graph

A Radio Mean labeling of a connected graph GG is a one to one map ff from the vertex set V(G)V(G) to the set of natural numbers NN such that for two distinct vertices uu and vv of GG, d(u,v)+⌈f(u)+f(v)2⌉≥1+diam(G). The radio mean number of ff, rmn(f)rmn(f), is the maximum number assigned to any vertex of GG.The radio mean number of GG, rmn(G)rmn(G) is the minimum value of rmn(f)rmn(f) taken over all radio mean labelings ff of GG. In this paper we find the radio mean number of graphs with diameter three, lotus inside a circle, Helms and Sunflower graphs.