# The Q-index and connectivity of graphs

@inproceedings{Zhang2021TheQA, title={The Q-index and connectivity of graphs}, author={Pengli Zhang and Lihua Feng and Weijun Liu and Xiaodong Zhang}, year={2021} }

A connected graph G is said to be k-connected if it has more than k vertices and remains connected whenever fewer than k vertices are deleted. In this paper, for a connected graph G with sufficiently large order, we present a tight sufficient condition for G with fixed minimum degree to be k-connected based on the Q-index. Our result can be viewed as a spectral counterpart of the corresponding Dirac type condition.

## One Citation

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This survey is two-fold. We first report new progress on the spectral extremal results on the Turán type problems in graph theory. More precisely, we shall summarize the spectral Turán function in…

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