- Full text PDF available (3)
- This year (2)
- Last 5 years (7)
- Last 10 years (9)
Journals and Conferences
In this note, we consider connected graphs with exactly two main eigenvalues. We will give several constructions for them, and as a consequence we show a family of those graphs with an unbounded number of distinct valencies.
Received by the editors on January 11, 2011. Accepted for publication on July 10, 2011. Handling Editor: Leslie Hogben. College of Mathematics and System Science, Xinjiang University, Urumqi, 830046, P.R. China (firstname.lastname@example.org, email@example.com, firstname.lastname@example.org). Supported by NFSC Grant No. 10961023. Electronic Journal of Linear Algebra ISSN… (More)
Two graphs G and H are called R-cospectral if A(G)+yJ and A(H)+yJ (where A(G), A(H) are the adjacency matrices of G and H, respectively, J is the all-one matrix) have the same spectrum for all y ∈ R. In this note, we give a necessary condition for having R-cospectral graphs. Further, we provide a sufficient condition ensuring only irrational orthogonal… (More)