The concept of geometric-arithmetic indices (GA) was put forward in chemical graph theory very recently. In spite of this, several works have already appeared dealing with these indices. In this paper we present lower and upper bounds on the second geometric-arithmetic index (GA2) and characterize the extremal graphs. Moreover, we establish Nordhaus-Gaddum-type results for GA2.

it is well known that the chemical behavior of a compound is dependent upon the structure of itsmolecules. quantitative structure – activity relationship (qsar) studies and quantitative structure –property relationship (qspr) studies are active areas of chemical research that focus on the nature ofthis dependency. topological indices are the numerical value associated with chemical constitution...

Simple random walks probabilistically grown step by step on a graph are distinguished from walk enumerations and associated equipoise random walks. Substructure characteristics and graph invariants correspondingly defined for the two types of random walks are then also distinct, though there often are analogous relations. It is noted that the connectivity index as well as some resistance-distan...

The stable marriage problem (SM) and its many variants are extensively-studied combinatorial problems with many practical applications. The n-dimensional stable marriage model is proposed, which is initially motivated by a problem arising from chemical graph theory, and an algorithm is given accordingly. This model solves the zero clustering problem of chemical graph polynomials successfully, w...

abstract. topological indices are the numerical value associated with chemical constitution purporting for correlation of chemical structure with various physical properties, chemical reactivity or biological activity. graph theory is a delightful playground for the exploration of proof techniques in discrete mathematics and its results have applications in many areas of sciences. one of the us...

It is well known that the chemical behavior of a compound is dependent upon the structure of itsmolecules. Quantitative structure – activity relationship (QSAR) studies and quantitative structure –property relationship (QSPR) studies are active areas of chemical research that focus on the nature ofthis dependency. Topological indices are the numerical value associated with chemical constitution...