English
The closure of s is contained in S if and only if s is contained in S for any subsemigroup S.
Русский
Замыкание s содержится в S тогда и только тогда, когда s содержится в S для любого underlined подполугруппы S.
LaTeX
$$$ \\mathrm{closure}(s) \\le S \\;\\iff\\; s \\subseteq S $$$
Lean4
/-- A subsemigroup `S` includes `closure s` if and only if it includes `s`. -/
@[to_additive (attr := simp) /-- An additive subsemigroup `S` includes `closure s` if and only if it includes `s` -/
]
theorem closure_le : closure s ≤ S ↔ s ⊆ S :=
⟨Subset.trans subset_closure, fun h => sInf_le h⟩