Erdős problem 347 · problems.science

Is there a sequence $A=\{a_1\leq a_2\leq \cdots\}$ of integers with $\lim \frac{a_{n+1}}{a_n}=2$ such that $P(A')= \left\{\sum_{n\in B}n : B\subseteq A'\textrm{ finite }\right\}$ has density $1$ for every cofinite subsequence $A'$ of $A$ ?

Workspace

Continue locally Open source Sign in to contribute

Open this exact Problem, source revision, and authority Repository in Workbench. This handoff does not clone, switch, upload, or execute anything.

Canvas

public preview

Source#347
→
ResultNone
→
Checks0

Reported activity

Work these sources record against this Problem. Source-reported attribution, not reviewed here.

AI collaborating with humans
Erdős AI contributions wiki · 25 Oct, 2025-4 Feb, 2026
Machine
Aristotle, Claude Opus, Codex, GPT
People
Enrique Barschkis, Wouter van Doorn, jbbaehr22, Bartosz Naskrecki, Terence Tao
Open the source record
argument
VibeMathed
Machine
Aristotle, Claude Opus, Codex, GPT
People
Enrique Barschkis, Wouter van Doorn, jbbaehr22, Bartosz Naskrecki, Terence Tao
Reported outcome
resolved
Open the source record

Reported activity

Search problems.science