PPL 069 / 177 permanent IDsPrize Problem Ledger · PPLChecked 2026.07.26
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Prize Problem LedgerErdősPPL 069Erdős Problem #634

Permanent problem IDPPL 069

Verified openErdősconjecture

Geometry

Erdős Problem #634

Find all n such that there is at least one triangle which can be cut into n congruent triangles.

geometry
01

The problem

Find all n such that there is at least one triangle which can be cut into n congruent triangles.

Open since1991source estimate
Last checked2026.07.26Catalog verification
02

Reward offers

Offer 01$25Paul Erdős / Combinatorics Foundation
Documented

A solution must appear in a reputable journal, with documentation that Erdős offered the displayed amount. Claims are administered by the Combinatorics Foundation; erdosproblems.com does not pay awards.

Award source ↗Rules ↗
03

Sources & reading

2 unique reference linksCanonical problem page Claim or award rules
04

Related open targets

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