Source labels openErdős Problems · Combinatorics
Erdős Problem 160: Better Lower
Estimate by finding a better lower bound.
Source checked Jul 26, 20261 pinned Lean statementInspect problem
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Erdős Problem 189: Parallelogram
Seems to be open, as of January 2025.
Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Combinatorics
Erdős Problem 633
Which triangles can only be decomposed into a square number of congruent triangles?
Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openWikipedia · Number theory
Rational distance problem
Does there exist a point in the plane at rational distance from all four vertices of the unit square?
Source checked Jul 26, 20261 pinned Lean statementInspect problem