English

Large book--cycle Ramsey numbers

Combinatorics 2021-02-08 v3

Abstract

Let Bn(k)B_n^{(k)} be the book graph which consists of nn copies of Kk+1K_{k+1} all sharing a common KkK_k, and let CmC_m be a cycle of length mm. In this paper, we first determine the exact value of r(Bn(2),Cm)r(B_n^{(2)}, C_m) for 89n+112m3n2+1\frac{8}{9}n+112\le m\le \lceil\frac{3n}{2}\rceil+1 and n1000n \geq 1000. This answers a question of Faudree, Rousseau and Sheehan (Cycle--book Ramsey numbers, {\it Ars Combin.,} {\bf 31} (1991), 239--248) in a stronger form when mm and nn are large. Building upon this exact result, we are able to determine the asymptotic value of r(Bn(k),Cn)r(B_n^{(k)}, C_n) for each k3k \geq 3. Namely, we prove that for each k3k \geq 3, r(Bn(k),Cn)=(k+1+ok(1))n.r(B_n^{(k)}, C_n)= (k+1+o_k(1))n. This extends a result due to Rousseau and Sheehan (A class of Ramsey problems involving trees, {\it J.~London Math.~Soc.,} {\bf 18} (1978), 392--396).

Keywords

Cite

@article{arxiv.1909.13533,
  title  = {Large book--cycle Ramsey numbers},
  author = {Qizhong Lin and Xing Peng},
  journal= {arXiv preprint arXiv:1909.13533},
  year   = {2021}
}

Comments

Journal Ref. SIAM J. Discrete Math

R2 v1 2026-06-23T11:29:55.477Z