English
If a nonunital subsemiring is commutative, its topological closure is a commutative semiring as well.
Русский
Если неполное подпол semiring коммутативно, то его топологическое замыкание тоже коммутативное полусемiring.
LaTeX
$$$\\mathrm{NonUnitalCommSemiring}(\\mathrm{Subtype}\\big( s.topologicalClosure\\big))$, under commutativity of multiplication$$
Lean4
/-- If a non-unital subsemiring of a non-unital topological semiring is commutative, then so is its
topological closure.
See note [reducible non-instances] -/
abbrev nonUnitalCommSemiringTopologicalClosure [T2Space R] (s : NonUnitalSubsemiring R)
(hs : ∀ x y : s, x * y = y * x) : NonUnitalCommSemiring s.topologicalClosure :=
{ NonUnitalSubsemiringClass.toNonUnitalSemiring s.topologicalClosure,
s.toSubsemigroup.commSemigroupTopologicalClosure hs with }