Wiki
Wiki

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

Updated


Claim. There is an infinite Sidon set S⊂NS\subset\mathbb{N}, a set in which a+b=c+da+b=c+d with a,b,c,d∈Sa,b,c,d\in S forces {a,b}={c,d}\{a,b\}=\{c,d\}, such that every sufficiently large integer is a sum of three elements of SS. This answers the question of Erdős, Sárközy and Sós yes, and the order is optimal, since no Sidon set is an asymptotic basis of order two. The construction in [[../library/additive_bases/pilatte_2023_solution_erdos_sarkozy_sos_problem_asymptotic/_index|Pilatte's paper]] starts from Cilleruelo's discrete-logarithm variant of Ruzsa's dense Sidon sequence, in its Fq[t]\mathbb{F}_q[t] form, and shows that a random choice succeeds with probability one (Theorem 5.4); purely probabilistic constructions almost surely fail to give an order-3 basis (p. 2), and the equidistribution input, which over the integers would need something like Montgomery's conjecture, comes from Sawin's theorem on the Fq[t]\mathbb{F}_q[t] analogue of Montgomery's conjecture for convolutions of the von Mangoldt function. Earlier constructions gave Sidon asymptotic bases of order 77, 55 and 44, and of every order 3+ε3+\varepsilon in the sense of Cilleruelo.

Depends on. No page of this wiki; the result is the paper's.

Acceptance. Refereed: C. Pilatte, A solution to the Erdős–Sárközy–Sós problem on asymptotic Sidon bases of order 3, Compositio Math. 160 (2024), no. 6, 1418–1432, published online 2024-05-10; the page name uses the date of the arXiv first version, 2023-03-16. Reviewed: the site's curator, T. F. Bloom, labels Problem 157 proved on this result at erdosproblems.com, which is the site's acceptance. The site records no formalization of the problem and formal-conjectures has no statement file for it. The linked outside Lean development (Erdos157.lean, pinned at its commit of 2026-08-25) states that Pilatte proved the theorem and cites this paper and Sawin's; its theorems erdos_157_of_sawinPrime_* follow this paper's route and each takes a hypothesis from Sawin's geometry, while its exported unconditional theorem Erdos157.erdos_157 is an earlier form of the elementary construction, with coefficients in the field of 210242^{1024} elements, of [[problems/additive_bases/E0157/claims/2026_08_25_alexeev|the AI-generated elementary proof of 2026]], not a formalization of this paper's argument. This corpus built and audited that unconditional theorem, in a later revision of the development, and records it as formal evidence on that page; the conditional theorems prove this paper's route only under their hypotheses, so formalized is not listed here.