Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Claim. Write for the largest prime factor of and for Dickman's function. For every fixed ,
the limit over all real with ordinary counting (Theorem 1.1 of the release's manuscript The joint Dickman law for consecutive integers, 2026-09-24, filed as the library's intake card). So the density asked for by Problem 928 exists and equals the product of the two Dickman densities: the events and are independent in the sense Erdős asked for, which the manuscript calls the Erdős–Pomerance joint Dickman conjecture. Its Section 11 also gives the law with the fixed thresholds and and the upper-tail independence that Erdős and Pomerance conjectured. Its Corollary 1.2, that has natural density , follows because the continuous limiting law gives the diagonal no mass; it is the question of Problem 371, which carries its own account. The method replaces the largest prime factor by finitely many counts of prime factors in bins , so that the joint law becomes a mixed decorrelation between two bin characters with different phase vectors, one centered; the decorrelation is proved through an amplification of the correlation over an auxiliary logarithmic scale, an independent-site kernel, a second moment for the latent rows, smoothing on logarithmic and residue space, and the vanishing of the main energy.
Bridge to the statement. The problem's set uses strict inequalities and the threshold for ; the manuscript and the Lean use and . Up to the two sets differ by at most integers: an in one set and not the other either has exactly, so that for a prime , or has equal to a prime with , an interval of length below that determines from . Both counts are , so the densities of the two sets agree. The bridge is elementary and is stated here, not in Lean.
Depends on. No page of this wiki.
Acceptance. Formalized. The release's lean/ folder states the theorem as
OAI.JointDickmanPaper.joint_law in the comparator challenge
JointDickman.lean (the third link), with the ordering corollaries
increasing_order and decreasing_order, proved in its solution module
OAI.NumberTheory.JointDickman.PaperMain (in the tree of the second link): the
predicate uses Mathlib's Nat.maxPrimeFac, the density counts
and divides by the real , and the Dickman
function is defined through its delay equation; the challenge's configuration
permits only propext, Quot.sound and Classical.choice. This corpus's
verification built OAI.JointDickmanPaper.joint_law at the pinned revision of 6
October 2026 with the toolchain leanprover/lean4:v4.34.1 and checked its
axioms, which are exactly those three, with no sorry; its fingerprint was
found identical to the challenge. The statement audit found the declaration
exactly Theorem 1.1 as displayed above, for every real , a
hypothesis that can be met: Nat.maxPrimeFac is the true largest prime factor
for every , and the count uses only ; realDensity is the
ordinary two-sided natural density over real , which leaving out does
not change; and the formal , built level by level from the value on
and the equation through continuous
approximants, so that its integrals are genuine and not junk values, is the
Dickman function, evaluated at and . The audit also checked the
bridge above, which is correct and is stated on this page, not in Lean; since
the Statement asks only whether the density exists, the theorem with the bridge
settles it in full. Not reviewed or refereed: no outside review, referee report
or acceptance by the site is known (the site labels the problem OPEN, its page
last edited 3 April 2026), and no review of the manuscript's proof is recorded.
The manuscript places the result against the earlier literature:
Teräväinen 2018
proved the product law in logarithmic density (Theorem 1.14 there) and the
ordering in logarithmic density ; Wang [Wa21] proved the natural density
under the Elliott–Halberstam conjecture for friable integers, the accepted
conditional claim on
Wang 2021; Tao
and Teräväinen obtained the ordinary law outside an exceptional set of scales;
and the lower natural density of each ordering rose from Erdős and Pomerance's
through the of
Lü and Wang
to in Yang's 2026 preprint (arXiv:2607.16032), none asserting that the
density exists. The release's README states that its manuscripts and supporting
proof artifacts were produced by an internal OpenAI model and that the
collection includes results at different stages of verification; the
manuscript's author line is OpenAI and names no person.