Yaoping Hou

collaborators

2 papers

math.CO2018

Unicyclic signed graphs with maximal energy

Dijian Wang, Yaoping Hou

Let $x_{1}, x_{2}, \dots, x_{n}$ be the eigenvalues of a signed graph $Γ$ of order $n$ . The energy of $Γ$ is defined as $E (Γ) = \sum_{j = 1}^{n} ∣ x_{j} ∣.$ Let $P_{n}^{4}$ be obtained by c…

math.CO2018

The graphs with all but two eigenvalues equal to $2$ or $- 1$

Jing Li, Deqiong Li, Yaoping Hou

In this paper, all graphs whose adjacency matrix has at most two eigenvalues (multiplicities included) different from $2$ and $- 1$ are determined. These graphs conclude a class of…

Unicyclic signed graphs with maximal energy

The graphs with all but two eigenvalues equal to 2 or −1

The graphs with all but two eigenvalues equal to $2$ or $- 1$