English
There is a natural equivalence between the index type ι and the quotient hs.Quotient, given by hs.equivQuotient.
Русский
Существует естественное биективное соответствие между индексным типом ι и квотиентом hs.Quotient, задаваемое hs.equivQuotient.
LaTeX
$$$ hs.equivQuotient : ι \simeq hs.Quotient $$$
Lean4
/-- The obvious equivalence between the quotient associated to an indexed partition and
the indexing type. -/
def equivQuotient : ι ≃ hs.Quotient :=
(Setoid.quotientKerEquivOfRightInverse hs.index hs.some <| hs.index_some).symm