English
There is an order-preserving equivalence between Subsemiring(R) and Subsemiring(R^op).
Русский
Существует упорядоченно-одинообразное соотношение между подпsemiring(R) и подпsemiring(R^op).
LaTeX
$$$\mathrm{Subsemiring}(R) \cong^{\mathrm{ord}} \mathrm{Subsemiring}(R^{\mathrm{op}})$$$
Lean4
/-- A subsemiring `S` of `R` determines a subsemiring `S.op` of the opposite ring `Rᵐᵒᵖ`. -/
@[simps]
def opEquiv : Subsemiring R ≃o Subsemiring Rᵐᵒᵖ
where
toFun := Subsemiring.op
invFun := Subsemiring.unop
left_inv := unop_op
right_inv := op_unop
map_rel_iff' := op_le_op_iff