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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 0<δ≤1/(6⋅84)0<\delta\le1/(6\cdot8^4) and XX large depending on δ\delta,

N(X,δ)>X1/2−δ1/7,N(X,\delta)>X^{1/2-\delta^{1/7}},

where N(X,δ)N(X,\delta) is the largest number of points in a disc of radius XX whose pairwise distances all lie at distance at least δ\delta from the nearest integer, as Problem 466 defines it. This is Theorem 1 of Part II (p. 106), quoted on the result page theorem_1, with its Corollary (p. 107): for every ε>0\varepsilon>0 there is δ0(ε)>0\delta_0(\varepsilon)>0 with N(X,δ)>X1/2−εN(X,\delta)>X^{1/2-\varepsilon} for 0<δ<δ0(ε)0<\delta<\delta_0(\varepsilon) and large XX. The digest is on the source card sarkozy_1976_distances_near_integers_ii. The exponent is positive throughout the range, so N(X,δ)→∞N(X,\delta)\to\infty as X→∞X\to\infty for every such δ\delta. The same paper (pp. 105--106) gives Graham's construction, the points (xi,xi2)(x_i,x_i^2) with x1=10x_1=10 and xn=2xn−1x_n=2x_{n-1}, which yields N(X,1/10)>110log⁡XN(X,1/10)>\frac1{10}\log X for large XX and is the result the site's commentary credits to Graham. Graham's argument has no publication of its own among the sources read: Sárközy alone sketches it, from Erdős's oral communication, while Erdős reports Graham's bound without a construction in the 1980 monograph and the 1982 survey. It is disclosed here and gets no page. The proof of Theorem 1 (pp. 107--110: points with coordinates built from digits in base k>δ−1/7k>\delta^{-1/7} and the Lemma on ∥a2+b2∥\|\sqrt{a^2+b^2}\|) is not checked here. The matching upper bounds are compiled on Problem 465.

Acceptance. Refereed: A. Sárközy, On distances near integers, II, Studia Sci. Math. Hungar. 11 (1976), 105--111, received 11 February 1976. Reviewed: the site's curator, Thomas F. Bloom, marks Problem 466 PROVED and credits Graham's proof and Sárközy's improvement in the problem's commentary (page last edited 16 September 2025); the curator neither wrote nor submitted the result. The 1980 monograph of Erdős and Graham and Konyagin's introduction of 2001 cite the bound as proved. Graham's construction has a third-party Lean formalization, linked above, whose header names Graham as the informal author and the AI systems Codex and GPT-5.6 Sol as the formal authors. It was not built here, so no formalized evidence is listed, and Theorem 1 itself is not formalized. The page is dated to the year of publication, since the volume prints no fuller date for the article; the paper link leads to the repository record of the volume scan.