New Families of tripartite graphs with local antimagic chromatic number 3

For a graph $G(V,E)$ of size q, a bijection f : E(G) → [1,q] is a local antimagc labeling if it induces a vertex labeling f⁺ : V(G) → N such that f⁺(u) ≠ f⁺(v), where f⁺(u) is the sum of all the incident edge label(s) of u, for every edge uv ∈ E(G). In this paper, we make use of matrices of fixed sizes to construct several families of infinitely many tripartite graphs with local antimagic chromatic number 3.