English
For a Noetherian local ring R and a proper ideal I ≠ ⊤, the intersection ∩_{i≥0} I^i equals ⊥.
Русский
Для Noetherian локального кольца R и подходящего идеала I ≠ ⊤, пересечение ∩_{i≥0} I^i равно нулю.
LaTeX
$$$[\\text{IsNoetherianRing } R]\\ [\\text{IsLocalRing } R]\\ (I \\neq \\top)\\Rightarrow \\bigcap_{i\\in\\mathbb{N}} I^i = \\bot.$$$
Lean4
/-- **Krull's intersection theorem** for Noetherian local rings. -/
theorem iInf_pow_eq_bot_of_isLocalRing [IsNoetherianRing R] [IsLocalRing R] (h : I ≠ ⊤) : ⨅ i : ℕ, I ^ i = ⊥ :=
by
convert I.iInf_pow_smul_eq_bot_of_isLocalRing (M := R) h
ext i
rw [smul_eq_mul, ← Ideal.one_eq_top, mul_one]