Approaches that output infinitely many graphs with small local antimagic chromatic number

An edge labeling of a connected graph G = (V, E) is said to be local antimagic if it is a bijection f :E -> {1, ..., vertical bar E vertical bar} such that for any pair of adjacent vertices x and y, f(+)(x) not equal f(+)(y), where the induced vertex label f(+)(x) = Sigma f(e), with e ranging over all the edges incident to x. The local antimagic chromatic number of G, denoted by chi(1a) (G), is the minimum number of distinct induced vertex labels over all local antimagic labelings of G. In this paper, we show the existence of infinitely many bipartite and tripartite graphs with chi(1a) = 2,3.