Mathlib Changelog
v4
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Commit
2025-07-31 16:18
bfadd55b
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feat:
f '' s = f ⁻¹' s
for an involution
f
(
#27746
)
Estimated changes
Modified
Mathlib/Data/Set/Image.lean
added
theorem
Function.Involutive.image_eq_preimage