Ordinal.cof_eq_sInf_lsub

Deprecated since 2026-03-27Mathlib marks this declaration as deprecated.

∀ (o : Ordinal.{u}), o.cof = sInf {a | ∃ ι f, Ordinal.lsub f = o ∧ Cardinal.mk ι = a}

Defined in: Mathlib.SetTheory.Cardinal.Cofinality.Ordinal
Cited by: 2 results in Mathlib
Foundations: Depth 92 from the axioms · uses propext, Classical.choice, Quot.sound

Around this declaration

Dashed lines are statement dependencies; solid lines are citations in proofs.

Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.

Results whose statement or proof uses this declaration.