Ebrahim Ghorbani

collaborators

Showing math.COShow all

2 papers · 1 filter

math.CO2009

Bounds for the Huckel energy of a graph

Ebrahim Ghorbani, Jack H. Koolen, Jae Young Yang

Let $G$ be a graph on $n$ vertices with $r := ⌊ n /2 ⌋$ and let $λ_{1} \geq ... \geq λ_{n}$ be adjacency eigenvalues of $G$ . Then the Hückel energy of $G$ , HE( $G$ ), is defi…

math.CO2007

Some Relations between Rank, Chromatic Number and Energy of Graphs

S. Akbari, E. Ghorbani, S. Zare

The energy of a graph $G$ , denoted by $E (G)$ , is defined as the sum of the absolute values of all eigenvalues of $G$ . Let $G$ be a graph of order $n$ and $rank (G)$ be the ran…