PPL 064 / 177 permanent IDsPrize Problem Ledger · PPLChecked 2026.07.26
Permanent problem IDPPL 064
Verified openErdősconjecture
Set theory
Erdős Problem #593
Characterize those finite 3-uniform hypergraphs which appear in every 3-uniform hypergraph of chromatic number >\aleph_0.
set theorygraph theoryhypergraphschromatic number
01
The problem
Characterize those finite 3-uniform hypergraphs which appear in every 3-uniform hypergraph of chromatic number >\aleph_0.
Open since1995exact
Last checked2026.07.26Catalog verification
02
Reward offers
Offer 01$500Paul Erdős / Combinatorics Foundation
DocumentedA 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.