Kaya, E.Maden, A. D.2020-03-262020-03-2620152228-64892008-9015https://hdl.handle.net/20.500.12395/31898In this paper, we present some inequalities for the Co-PI index involving the some topological indices, the number of vertices and edges, and the maximum degree. After that, we give a result for trees. In addition, we give some inequalities for the largest eigenvalue of the Co-PI matrix of G.eninfo:eu-repo/semantics/closedAccessCo-PI indexCo-PI matrixCo-PI spectral radiusArticle61113#YOKWOS:000371149500001N/A