Sharif University of Technology

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20022009

most citedf(R) Gravity: From the Pioneer Anomaly to the Cosmic Acceleration

74 citations

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6 papers · 1 filter

math.CO2009★ 3 cited

Cycles are determined by their domination polynomials

Saieed Akbari, Mohammad Reza Oboudi

Let $G$ be a simple graph of order $n$ . A dominating set of $G$ is a set $S$ of vertices of $G$ so that every vertex of $G$ is either in $S$ or adjacent to a vertex in $S$ . The dom…

math.CO2007

Choice Number and Energy of Graphs

Saieed Akbari, Ebrahim Ghorbani

The energy of a graph G, denoted by E(G), is defined as the sum of the absolute values of all eigenvalues of G. It is proved that E(G)>= 2(n-χ(\bar{G}))>= 2(ch(G)-1) for every grap…

math.CO2007

Inclusion Matrices and Chains

E. Ghorbani, G. B. Khosrovshahi, Ch. Maysoori +1

Given integers $t$ , $k$ , and $v$ such that $0 \leq t \leq k \leq v$ , let $W_{t k} (v)$ be the inclusion matrix of $t$ -subsets vs. $k$ -subsets of a $v$ -set. We modify slightly the concep…

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…

math.CO2006★ 17 cited

Circular chromatic index of graphs of maximum degree 3

Peyman Afshani, Mahsa Ghandehari, Mahya Ghandehari +3

This paper proves that if $G$ is a graph (parallel edges allowed) of maximum degree 3, then $χ_{c}^{'} (G) \leq 11/3$ provided that $G$ does not contain $H_{1}$ or $H_{2}$ as a subgraph, whe…

math.CO2006

On the size of the minimum critical set of a Latin square

Mahya Ghandehari, Hamed Hatami, Ebadollah S. Mahmoodian

A critical set in an $n \times n$ array is a set $C$ of given entries, such that there exists a unique extension of $C$ to an $n \times n$ Latin square and no proper subset of $C$ h…