English
If I and S are disjoint, there exists a prime p containing I with p disjoint from S.
Русский
Если I и S не пересекаются, существует primeside p содержательный I и disjoint с S.
LaTeX
$$$\exists p:\ Ideal\ α, p.IsPrime \land I \le p \land Disjoint (p) S$$$
Lean4
theorem exists_disjoint_powers_of_span_eq_top (s : Set α) (hs : span s = ⊤) (I : Ideal α) (hI : I ≠ ⊤) :
∃ r ∈ s, Disjoint (I : Set α) (Submonoid.powers r) :=
by
have ⟨M, hM, le⟩ := exists_le_maximal I hI
have := hM.1.1
rw [Ne, eq_top_iff, ← hs, span_le, Set.not_subset] at this
have ⟨a, has, haM⟩ := this
exact ⟨a, has, Set.disjoint_left.mpr fun x hx ⟨n, hn⟩ ↦ haM (hM.isPrime.mem_of_pow_mem _ (le <| hn ▸ hx))⟩