Source labels openMathOverflow · Category theory
Mathoverflow 31809
Does there exist a category that is pretriangulated but not triangulated?
Source checked Jul 26, 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.Does there exist a category that is pretriangulated but not triangulated?