4 papers
A family of regular integral graphs and its application to the -Queens' graph
Domingos M. Cardoso, Inês Serôdio Costa, Rui Duarte
A family of regular integral graphs introduced in [I.F.S. Costa, The -Queens graph and its generalizations, Ph.D. Thesis, University of Aveiro 2024], denoted by an…
Integer eigenvalues of the -Queens graph
Domingos M. Cardoso, Inês Serôdio Costa, Rui Duarte
The -Queens graph, , is the graph obtained from a chessboard where each of its squares is a vertex and two vertices are adjacent if and only if…
Sharp bounds on the least eigenvalue of a graph determined from edge clique partitions
Domingos M. Cardoso, Inês Serôdio Costa, Rui Duarte
Sharp bounds on the least eigenvalue of an arbitrary graph are presented. Necessary and sufficient (just sufficient) conditions for the lower (upper) bound to be attained are deduc…
Spectral properties of the -Queens' Graphs
Domingos M. Cardoso, Inês Serôdio Costa, Rui Duarte
The -Queens' graph, , is the graph associated to the chessboard (a generalization of the classical chessboard), with vertices, ea…