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arXiv · 2111.03309

A survey on spectral conditions for some extremal graph problems

Yongtao Li·Weijun Liu·Lihua Feng
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Abstract

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 terms of the adjacency spectral radius and the signless Laplacian spectral radius for various graphs. For instance, the complete graphs, general graphs with chromatic number at least three, complete bipartite graphs, odd cycles, even cycles, color-critical graphs and intersecting triangles. The second goal is to conclude some recent results of the spectral conditions on some graphical properties. By a unified method, we present some sufficient conditions based on the adjacency spectral radius and the signless Laplacian spectral radius for a graph to be Hamiltonian, $k$-Hamiltonian, $k$-edge-Hamiltonian, traceable, $k$-path-coverable, $k$-connected, $k$-edge-connected, Hamilton-connected, perfect matching and $β$-deficient.

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Yongtao Li, Weijun Liu, Lihua Feng. 2022-05-12. A survey on spectral conditions for some extremal graph problems. https://doi.org/10.11845/sxjz.2021005a

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