This paper intends to study the relation between PRN and chromatic number of planar graphs. In this regard we investigate that isomorphic or 1 isomorphic graph may or may not have equal PRN and few other related results. Precisely, we give simple proof of Four Color Map Theorem.
The Bulletin of Society for Mathematical Services and Standards (Volume 11)
H.R. Bhapkar and J.N. Salunke, "Proof of Four Color Map Theorem by Using PRN of Graph", The Bulletin of Society for Mathematical Services and Standards, Vol. 11, pp. 26-30, 2014