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arXiv · 2604.19409

The high order spectral extrema of $2K_r$-free graphs

Changjiang Bu·Yifan Sun·Haotian Zeng
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Abstract

In this paper, we determine the graphs with maximum value of the sum number from $k$-clique spectral radius to $(2r-1)$-clique spectral radius among all $2K_{r}$-free graphs on $n$ vertices for $ r\le k$ and large $n$. We also determine the graphs with maximum $3$-clique spectral radius among all $2K_{3}$-free graphs on $n$ vertices. Our results are spectral versions of some results on generalized Turán numbers.

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Changjiang Bu, Yifan Sun, Haotian Zeng. 2026-04-21. The high order spectral extrema of $2K_r$-free graphs. https://arxiv.org/abs/2604.19409

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