title: PI polynomial of V-phenylenic nanotubes and nanotori.
abstract: The PI polynomial of a molecular graph is defined to be the sum X(|E(G)|-N(e)) + |V(G)|(|V(G)|+1)/2 - |E(G)| over all edges of G, where N(e) is the number of edges parallel to e. In this paper, the PI polynomial of the phenylenic nanotubes and nanotori are computed. Several open questions are also included.
authors.affiliation: The Organization for Educational Research and Planning (OERP), Iran.
authors.forename: Vahid
authors.initials: V
authors.lastname: Alamian
authors.affiliation: Department of Mathematics, Islamic Azad University, Garmsar Branch, Garmsar, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Bahrami
authors.affiliation: Department of Mathematics and Statistics, Shahid Beheshti University, Tehran, Iran.
authors.forename: Behrooz
authors.initials: B
authors.lastname: Edalatzadeh