Extremal Values of VDB Topological Indices over Catacondensed Polyomino Systems
نویسندگان
چکیده
A VDB topological index is defined as
منابع مشابه
Extremal Polyomino Chains of VDB Topological Indices
We show that the zig-zag chain Z3 n of segments of length 3 (see Figure 2) has the minimal ABC index among all polyomino chains with n squares. More generally, we give conditions on the numbers {φij} under which the zig-zag chain Z3 n is an extremal value of the induced topological index T defined by T (G) = ∑ 1≤i≤j≤n−1 mijφij where G is a graph with n vertices and mij is the number of edges of...
متن کاملThe Linear Chain as an Extremal Value of VDB Topological Indices of Polyomino Chains
We give conditions on the numbers {φij} under which a vertexdegree-based topological index TI of the form
متن کاملA note on the zeroth-order general randić index of cacti and polyomino chains
The present note is devoted to establish some extremal results for the zeroth-order general Randi'{c} index of cacti, characterize the extremal polyomino chains with respect to the aforementioned index, and hence to generalize two already reported results.
متن کاملSecond and Third Extremals of Catacondensed Hexagonal Systems with Respect to the PI Index
The Padmakar-Ivan (PI) index is a Wiener-Szeged-like topological index which reflects certain structural features of organic molecules. The PI index of a graph G is the sum of all edges uv of G of the number of edges which are not equidistant from the vertices u and v. In this paper we obtain the second and third extremals of catacondensed hexagonal systems with respect to the PI index.
متن کاملTopological indices of Kragujevac trees
We find the extremal values of the energy, the Wiener index and several vertex-degree-based topological indices over the set of Kragujevac trees with the central vertex of fixed degree. 2010 Mathematics Subject Classification : 05C90, 05C35.
متن کامل