Theorems · Definition · logic and foundations
Ordinal.preOmega
Ordinal.{u} ↪o Ordinal.{u}The "pre-omega" function gives the initial ordinals listed by their ordinal index.
preOmega n = n, preOmega ω = ω, preOmega (ω + 1) = ω₁, etc.
For the more common omega function skipping over finite ordinals, see Ordinal.omega.
- Defined in
- Mathlib.SetTheory.Cardinal.Aleph
- Cited by
- 31 results in Mathlib
- Foundations
- Depth 87 from the axioms · uses propext, Classical.choice, Quot.sound
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites5
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- Set.ofPredproof · cited by 6,101
- Ordinalstatement and proof · cited by 1,688
- OrderEmbeddingstatement · cited by 619
- Ordinal.IsInitialproof · cited by 28
- Ordinal.enumOrdproof · cited by 23
Cited by32
Results whose statement or proof uses this declaration.
- Ordinal.omegaproof · cited by 60
- Ordinal.lift_omegaproof · cited by 12
- Cardinal.ord_preAlephstatement and proof · cited by 5
- Ordinal.card_preOmegastatement · cited by 4
- Ordinal.preOmega_omega0statement · cited by 4
- Ordinal.isNormal_preOmegastatement and proof · cited by 3
- Ordinal.omega_eq_preOmegastatement · cited by 3
- Ordinal.omega_zeroproof · cited by 3
- Ordinal.preOmega_natCaststatement and proof · cited by 3
- Ordinal.isInitial_preOmegastatement · cited by 3
- Ordinal.preOmega_le_preOmegastatement and proof · cited by 2
- Ordinal.preOmega_lt_preOmegastatement and proof · cited by 2