Izvorni znanstveni članak
Tricyclic biregular graphs whose energy exceeds the number of vertices
Snježana Majstorović
orcid.org/0000-0002-3083-0932
; Department of Mathematics, University of Osijek,Osijek, Croatia
Ivan Gutman
; Faculty of Science, University of Kragujevac, Kragujevac, Serbia
Antoaneta Klobučar
; Department of Mathematics, University of Osijek,Osijek, Croatia
Sažetak
The eigenvalues of a graph are the eigenvalues of its adjacency matrix. The energy $E(G)$ of the graph $G$ is the sum of the absolute values of the eigenvalues of $G$. A graph is said to be $(a,b)$-biregular if its vertex degrees assume exactly two different values: a and b. A connected graph with $n$ vertices and $m$ edges is tricyclic if m=n+2. The inequality $E(G)\geq n$ is studied for connected tricyclic biregular graphs, and conditions for its validity are established.
Ključne riječi
energy (of a graph); biregular graph; tricyclic graph
Hrčak ID:
53226
URI
Datum izdavanja:
10.6.2010.
Posjeta: 1.394 *