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Theorem cardinal.le_aleph_0_iff_set_countable

Modification history

2022-09-12 11:04
src/set_theory/cardinal/basic.lean
refactor(set_theory/basic): match `x < ℵ₀` lemmas with `x ≤ ℵ₀` lemmas (#15662) …
Added cardinal.le_aleph_0_iff_set_countableView on Github →