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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Claim. For every fixed r≥2r\ge2 there are constants B,b>0B,b>0, depending only on rr, such that for every sufficiently large nn some graph of order nn and size O(n)O(n) has, in every rr-coloring of its edges, a color containing induced monochromatic cycles of every length between Blog⁡nB\log n and bnbn (Theorem 10; its Lemma 9 supplies the graph for every large nn, and the introduction states it for every n≥1n\ge1); hence the induced size Ramsey number satisfies reind(Cℓ,r)≤crℓr_e^{\mathrm{ind}}(C^\ell,r)\le c_r\ell (Corollary 11), and in two colors r^(Cℓ)=O(ℓ)\hat r(C_\ell)=O(\ell). The abstract adds that this settles the conjecture of Graham and Rödl that the induced size-Ramsey number of the path PℓP^\ell of order ℓ\ell is linear. Deleting a vertex of an induced monochromatic cycle leaves an induced monochromatic path, so in two colors r^(Pn)=O(n)\hat r(P_n)=O(n) too. The results are paged at Theorem 10 and Corollary 11 of the library's source card, whose page numbers are the authors' preprint's, not the journal's.

Scope. Full: all three questions of Problem 720. Since r^(Pn)=O(n)\hat r(P_n)=O(n), (i) is answered no and (ii) yes. Since r^(Cn)=O(n)\hat r(C_n)=O(n), (iii) is answered yes. The value is solved because one answer is no and the others yes. The paper proves no separate theorem about paths, though it quotes Beck's linear bound re(Pℓ,r)≤crℓr_e(P^\ell,r)\le c_r\ell (p. 2) and says its main result settles Graham and Rödl's question whether a linear bound also holds for induced Ramsey numbers of paths (abstract; p. 2). Beck's earlier path bound has its own claim page, and the site credits Beck with the cycle bound too. This paper (p. 3) attributes the plain, non-induced linear bound for cycles to Bollobás, Burr and a third person the preprint leaves unnamed and the published abstract names as Reimer, as a personal communication of November 1992, and says its proof of Theorem 10 can be simplified to a direct proof of that bound; it is the first published proof of r^(Cn)=O(n)\hat r(C_n)=O(n) among the sources read. Explicit constants came later: Javadi, Khoeini, Omidi and Pokrovskiy give r^(Cn)≤105⋅cn\hat r(C_n)\le10^5\cdot cn for large nn with c=6.5c=6.5 for even and c=1989c=1989 for odd nn (Combin. Probab. Comput. 28 (2019)), improving the 106⋅cn10^6\cdot cn with c=843c=843 and c=113482c=113482 of their 2017 preprint.

Depends on. Nothing in this wiki; the result is the paper's own theorem.

Dating. The page is dated by the issue month of the journal record (Combin. Probab. Comput. 4 (1995), no. 3, September 1995, per the Crossref record); the day in the page name is a placeholder.

Acceptance. Refereed: Combin. Probab. Comput. 4 (1995), no. 3, 217--239. Semantic Scholar's roughly 95 citing records (titles, 2026-09-18) include no dispute. The site's commentary does not cite the paper; it credits the cycle bound to Beck.

Read depth. Claims checked: the basis is Theorem 10 and Corollary 11 (preprint p. 11) and the attribution (p. 3 and reference [6], p. 21); no proof is covered, and nothing is independently reviewed in this corpus. The journal text is not compared with the preprint.