Open problemEditorial · Geometry and topology
Inscribed Square Problem
Every Jordan curve contains four points that are the vertices of a nondegenerate square.
Source checked Jul 24, 20261 pinned Lean statementInspect problem
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sorry marks an admitted statement, not a proof. Source indexing does not mean the formulation has been independently built or certified by Therefore.Every Jordan curve contains four points that are the vertices of a nondegenerate square.