Zulip Chat Archive
Stream: Is there code for X?
Topic: A lemma about ultrafilters
Adam Topaz (Oct 05 2020 at 02:17):
Does mathlib have the following variant of exists_ultrafilter
? I couldn't find anything similar.
lemma exists_ultrafilter' (S : set (set α)) (cond : ∀ T : finset (set α),
↑T ⊆ S → ⋂₀ (↑T : set (set α)) ≠ ∅) : ∃ F : filter α, S ⊆ F.sets ∧ is_ultrafilter F := sorry
Adam Topaz (Oct 05 2020 at 02:22):
If not, I could open a PR for this:
https://github.com/leanprover-community/mathlib/blob/b85798964d03672dc8c3123ccdd5a7fa2916f2eb/src/order/filter/ultrafilter.lean#L145
Adam Topaz (Oct 05 2020 at 14:24):
Last updated: Dec 20 2023 at 11:08 UTC