In this paper, at first we mention to some results related to PI and vertex Co-PI indices and then we introduce the edge versions of Co-PI indices. Then, we obtain some properties about these new indices.

Domination is an ancient graph theoretical topic with applications in psychology, political sci- ence, and human behaviour. A topological index area of theory that governs a compound’s molecular structure. This work aims to conglomerate the two different branches determine dominational variants some celebrated degree based index. The newly described descriptors are generalised standard graphs, ...

The conjecture Σuv V(G) dG(u)2 / n(G) ≤ Σuvv E(G) dG(u)dG(v) / m(G) that compares normalized Zagreb indices attracted recently a lot of attention1-9. In this paper we analyze analogous statement in which degree dG(u) of vertex u is replaced by its eccentricity δG(u) in which way we define novel first and second Zagreb eccentricity indices. We show that Σuv V(G) εG(u)2 / n(G) ≥ Σuvv E(G) εG(u)εG...