Teória grafov v chémii
The Estrada Index
The full nonrigid group theory for trimethylamine.
The fundamental group and Galois coverings of hexagonal systems in 3-space.
The number of -matchings in almost every tree is a zero residue.
The stability of some chemical systems established by the semi-empirical method.
The Wiener number of Kneser graphs
The Wiener number of a graph G is defined as 1/2∑d(u,v), where u,v ∈ V(G), and d is the distance function on G. The Wiener number has important applications in chemistry. We determine the Wiener number of an important family of graphs, namely, the Kneser graphs.
The Wiener number of powers of the Mycielskian
The Wiener number of a graph G is defined as , d the distance function on G. The Wiener number has important applications in chemistry. We determine a formula for the Wiener number of an important graph family, namely, the Mycielskians μ(G) of graphs G. Using this, we show that for k ≥ 1, , where Sₙ, Tₙ and Pₙ denote a star, a general tree and a path on n vertices respectively. We also obtain Nordhaus-Gaddum type inequality for the Wiener number of .