Formulas for the Number of Weak Homomorphisms from Paths to Rectangular Grid Graphs

Penying Rochanakul, Hatairat Yingtaweesittikul, Sayan Panma

A weak homomorphism from a graph G to a graph H is a mapping f from V(G) to V(H), where either f(x) = f(y) or {f(x), f(y)} is an element of E(H), and this holds for all {x, y} in E…