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Theorems · Theorem · logic and foundations

Ordinal.lt_one_iff_zero

Deprecated since 2026-03-24Use Order.lt_one_iff instead.

∀ {a : Ordinal.{u_1}}, a < 1 ↔ a = 0
Defined in
Mathlib.SetTheory.Ordinal.Basic
Cited by
1 results in Mathlib
Foundations
Depth 38 from the axioms · uses propext, Classical.choice, Quot.sound
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Around this declaration

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Ordinal.IsFundamentalSequence.succ · cited by 0IsFundamentalSequence.succOrdinal · cited by 1688OrdinalOrder.lt_one_iff · cited by 14Order.lt_one_iffOrdinal.lt_one_iff_zeroCITED BYCITES

Cites2

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Cited by1

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