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arXiv · 2602.10499

Ramsey numbers of K_s + mK_t versus K_n

Lulu Dai·Qizhong Lin
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Abstract

For integers m >= 1, s >= 0, and t >= 1, let K_s + mK_t denote the join of a clique K_s and m vertex-disjoint copies of K_t. We prove that for fixed m >= 1, t >= 1, and s >= 0, R(K_s + mK_t, K_n) = O( n^{s+t-1} / (log n)^{s+t-2} ). This settles a problem proposed by Liu and Li (2026). Moreover, for (s,t) = (0,3) the bound is tight up to a constant factor, matching the classical result R(K_3, K_n) = Theta( n^2 / log n ) of Kim (1995).

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Lulu Dai, Qizhong Lin. 2026-02-11. Ramsey numbers of K_s + mK_t versus K_n. https://arxiv.org/abs/2602.10499

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