One of the most widely known topological index is the Wiener index. The Wiener Index Conjecture states that all positive integer numbers except a finite set are the Wiener indices of some trees. We explore the Wiener indices of the binary trees. We present efficient algorithms for generating the Wiener indices of the binary trees. Based on experiments we strengthen the conjecture for the class ...

Publisher: School of Statistics, Renmin University China, Journal: Journal Data Science, Title: The Matrix Expression, Topological Index and Atomic Attribute Molecular Structure, Authors: Qian-Nan Hu, Yi-Zeng Liang, Kai-Tai

A new topological index J (based on distance sums s i as graph invariants) is proposed. For unsaturated or aromatic compounds, fractional bond orders are used in calculating s i. The degeneracy of J is lowest among all single topological indices described so far. The asymptotic behaviour of J is discussed, e.g. when n ~ ~ in CnH2n+2, J ~ ~r for linear alkanes, and J ~ ** for highly branched ones.

topological distance and Li = L0,i −NH,i + qi is a local atom index (a characteristics of atom i) calculated from the atom valence, L0,i, the number of hydrogen atoms attached to atom, NH,i, and qi which is the corresponding charge density. The partial charges are computed by the topological empirical method of Gasteiger-Marsili [2] calculated with a fixed number of iterations. The CTI index co...

We generalize the coincidence semi-index introduced in [D-J] to pairs of maps between topological manifolds. This permits extending the Nielsen theory to this class of maps. Introduction. In this paper we generalize the coincidence semi-index theory, introduced in [D-J] in the smooth case, to pairs of maps between topological manifolds. It will be based on the topological transversality lemma (...

Among topological descriptors connectivity topological indices are very important and they have a prominent role in chemistry. One of them is atom-bond connectivity (ABC) index defined as ABC(G)= [formula:see text], in which degree of vertex v denoted by dv . Recently, a new version of atom-bond connectivity (ABC4) index was introduced by M. Ghorbani et.al in 2010 and is defined as ABC4(G)= [fo...