15 citations · 89 across the 39 of their papers we have counts for
4 papers · 1 filter
The spectrum and toughness of regular graphs
Sebastian M. Cioabă, Wiseley Wong
In 1995, Brouwer proved that the toughness of a connected -regular graph is at least , where is the maximum absolute value of the non-trivial eigenvalues of .…
Edge-disjoint spanning trees and eigenvalues of regular graphs
Sebastian M. Cioabă, Wiseley Wong
Partially answering a question of Paul Seymour, we obtain a sufficient eigenvalue condition for the existence of edge-disjoint spanning trees in a regular graph, when $k\in \{2…
Disconnecting strongly regular graphs
Sebastian M. Cioabă, Jack H. Koolen, Weiqiang Li
In this paper, we show that the minimum number of vertices whose removal disconnects a connected strongly regular graph into non-singleton components, equals the size of the neighb…
The graphs with all but two eigenvalues equal to
Sebastian M. Cioabă, Willem H. Haemers, Jason Vermette +1
We determine all graphs whose adjacency matrix has at most two eigenvalues (multiplicities included) different from and decide which of these graphs are determined by their…