Title
Boundary graphs—II: the limit case of a spectral property
Abstract
Recently, several results bounding the diameter of a regular graph from its eigenvalues have been presented. They admit the following unified presentation: Let λ 0 > λ 1 > … > λ d be the d + 1 distinct eigenvalues of a graph of order n and diameter D , and let P be a polynomial. Then, P ( λ 0 ) > ‖ P ‖ ∞ ( n −1) ⇒ D ⩽ dgr P , where where ‖ P ‖ ∞ = max 1 ⩽ i ⩽ d {| P ( λ i )|}. The best results are obtained when P = P k is the so-called k -alternating polynomial of degree k . For not necessarily regular graphs the above condition reads P k ( λ 0 ) > ‖ P k ‖ ∞ (‖ v ‖ 2 − 1) ⇒ D ⩽ k , where v is the positive eigenvector with smallest component equal to 1. To measure the accuracy of this result it seems interesting to investigate the graphs for which P k ( λ 0 ) = ‖ P k ‖ ∞ (‖ v ‖ 2 − 1), that we call boundary graphs. This has already been done for k = d − 1, and is undertaken in this paper for 1 ⩽ k < d − 1. We present several families of such graphs, paying special attention to graphs with diameter D = k + 1.
Year
DOI
Venue
1998
10.1016/S0012-365X(97)00153-2
Discrete Mathematics
Keywords
DocType
Volume
limit case,spectral property,boundary graph
Journal
182
Issue
ISSN
Citations 
1-3
Discrete Mathematics
12
PageRank 
References 
Authors
1.08
4
3
Name
Order
Citations
PageRank
M. A. Fiol181687.28
E. Garriga216419.92
J. L.A. Yebra329136.48