On local antimagic total labeling of complete graphs amalgamation

Let G = (V,E) be a connected simple graph of order p and size q. A graph G is called local antimagic (total) if G admits a local antimagic (total) labeling. A bijection g : E → {1, 2, . . . , q} is called a local antimagic labeling of G if for any two adjacent vertices u and v, we have $ g^+ (u) \ne g^+ (v) $, where $ g^+ (u) = \Sigma_{e∈E(u)} \text{ } g(e) $, and E(u) is the set of edges incident to u. Similarly, a bijection f : V (G)∪E(G) → {1, 2, . . . , p+q} is called a local antimagic total labeling of G if for any two adjacent vertices u and v, we have $ w_f (u) \ne w_f (v) $, where $ w_f (u) = f(u) + \Sigma_{e∈E(u)} f(e) $. Thus, any local antimagic (total) labeling induces a proper vertex coloring of G if vertex v is assigned the color $g^+ (v) $ (respectively, $ w_f (u) $). The local antimagic (total) chromatic number, denoted $χ_\text{la } (G) $ (respectively $χ_\text{lat } (G) $ ), is the minimum number of induced colors taken over local antimagic (total) labeling of G. In this paper, we determined $ χ_\text{lat } (G) $ where G is the amalgamation of complete graphs. Consequently, we also obtained the local antimagic (total) chromatic number of the disjoint union of complete graphs, and the join of $ K_1 $ and amalgamation of complete graphs under various conditions. An application of local antimagic total chromatic number is also given.