Document Type : Research Paper
Islamic Azad University, Shahr-e Rey Branch, Tehran, Iran.
Mathematics and Informatics Research Group, ACECR, Tarbiat Modares University, B.O. Box: 14115- 343, Tehran, Iran.
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.