Cofinite.lean`

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L4DEL: Lean4 Domain Explanation Language

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Project sources: Pinned project documentation, Pinned FLT blueprint introduction

2 declarations, 0 contain sorry, 0 declared as axioms

Cofinite

Material destined for Mathlib.

Imports (1)

Mathlib.Order.Filter.Cofinite

Imported by 2 files

lemma Filter.cofinite.sets.countable TODO upstream line 19 source
Source comment
TODO upstream

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Countable, Set.Countable, Set, Filter.sets, Filter.cofinite
Proof uses: Set.Countable.mono, Membership.mem, Set.Countable.preimage_of_injOn, Set.ofPred, Set.Finite, Set.Countable.ofPred_finite, Compl.compl, Function.Injective.injOn, And.left, Function.Injective, Function.Surjective, compl_bijective, Set.preimage
4 instances, coercions and auxiliary constants left out.

Tactic trace: 2 steps
Open to load the checked before-and-after goal states.
```
lemma Filter.cofinite.sets.countable (ι : Type*) [Countable ι] :
    (Filter.cofinite : Filter ι).sets.Countable :=
…
```
instance (instance at line 24) line 24 source