Erdős Problem #306

Erdős problem #306 · erdosproblems.com/306

If $a/b \in \mathbb{Q}_{>0}$ and $b$ is squarefree, can $a/b$ always be written as a finite sum of reciprocals of distinct products of two distinct primes?

Result

Proved

Status

Candidate (review pending)

AI contribution

AI-assisted

Method

Argument

Field

Number Theory, Unit Fractions

Posed by

—

Year posed

1980

Years open

46y

Solved

2026-06-19

Model

AI-assisted Lean development (models not itemized)

Vendor

—

Collaborators

—

Verification

Lean-verified

Publication

Announced

Significance

10 / 100*

Disclosed cost

—

Wikipedia

No dedicated article