Mohammad Reza Farahani, The Second-Connectivity and Second-Sum-Connectivity Indices of Armchair Polyhex Nanotubes TUAC6[m,n], ILCPA Volume 30, International Letters of Chemistry, Physics and Astronomy (Volume 30) https://www.scipress.com/ILCPA.30.74 Abstract: The m-connectivety and m-sum connectivity indices of G are defined as to be and where runs over all paths of length <i>m</i> in <i>G</i> and <i>d<sub>i</sub></i> is the degree of vertex <i>ν</i><i><sub>i</sub></i><i>.</i> In this paper, we give explicit formulas for the second-connectivity and second-sum-connectivity indices of an infinite class of Armchair Polyhex Nanotubes <i>TUAC<sub>6</sub>[m,n].</i> Keywords: Armchair Polyhex Nanotubes, M-Connectivety Index, Molecular Graph, M-Sum Connectivity Index