A Matrix Approach to Vertex-Degree-Based Topological Indices

A VDB (vertex-degree-based) topological index over a set of digraphs H is a function φ : H → R, defined for each H ∈ H as φ(H) =12 ∑uv∈Eφd+u d−v, where E is the arc set of H, d +u and d−v denote the out-degree and in-degree of vertices u and v respectively, and φij = f(i, j) for an appropriate real...