Status
On this page
Status
Topics
Status
On this page
Status
Topics
Let be a set such that . Let
If then is it true that
exists (and is finite)?
Source: erdosproblems.com/489
A full solution has been claimed but not yet accepted. The statement is true.
OPEN, in the site's label. The site notes that for the set of
prime squares, when is the squarefree numbers, Erdős proved the limit exists
(Publ. Math. Debrecen 2 (1951), 103--109; claim page
Erdős's squarefree case,
accepted and partial). A full proof claim posted to the site's proof-claims tab
on 15 July 2026 by Colin Snyder, produced with GPT 5.6 (custom harness), as the
tab names the system, answers yes with a Lean 4 proof bundle; the site has not
accepted it, nothing was built or audited here, and the claim page
Snyder's Lean proof
records it, together with the formal-conjectures collection's marking of the
problem as solved on the strength of a hosted copy of that proof, which is not
acceptance. A note of 20 April 2026 by Przemyslaw Chojecki, produced with
GPT-5.4 Pro, as Chojecki's thread comment says, claims a proof that the limit
always exists in and is finite for a structured class of ; it
is the partial claim page
Chojecki's note.
The frontmatter standing derives from the pending full claim, and it departs
from the label for that reason: Snyder's claim answers the Statement yes and
would settle it, so the derived standing is claimed with claim proved, while
the site, which has not accepted the claim, labels the problem OPEN.