Maxima of the Q-index: forbidden 4-cycle and 5-cycle

2013/08/07 by de Freitas, Maria Aguieiras A., Nikiforov, Vladimir, Patuzzi, Laura · 2 citations
#05C50 #Combinatorics (math.CO) #FOS: Mathematics

paper · doi:10.48550/arxiv.1308.1652

Abstract

This paper gives tight upper bounds on the largest eigenvalue q(G) of the signless Laplacian of graphs with no 4-cycle and no 5-cycle. If n is odd, let F_n be the friendship graph of order n; if n is even, let F_n be F_n-1 with an edge hanged to its center. It is shown that if G is a graph of order n, with no 4-cycle, then q(G)

Cited by

• The α-spectral Turán type problems for graphs
• Some Turán-type results for signless Laplacian spectral radius

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