Ordinal.cof_lsub_def_nonempty

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

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

The set in the lsub characterization of cof is nonempty.

Defined in: Mathlib.SetTheory.Cardinal.Cofinality.Ordinal
Cited by: 3 results in Mathlib
Foundations: Depth 88 from the axioms · uses propext, Classical.choice, Quot.sound

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