English
IsNilpotent of a top Lie subalgebra is equivalent to IsNilpotent of the Lie algebra itself.
Русский
Нильпотентность топового подалгебра эквивалентна нильпотентности самой алгебры.
LaTeX
$$[@simp] isNilpotent_of_top_iff' : IsNilpotent (LieSubalgebra.top) M ↔ IsNilpotent L M$$
Lean4
instance (priority := 100) isSolvable_of_isNilpotent (L : Type v) [LieRing L] [hL : LieModule.IsNilpotent L L] :
LieAlgebra.IsSolvable L :=
by
obtain ⟨k, h⟩ : ∃ k, LieModule.lowerCentralSeries ℤ L L k = ⊥ := hL.nilpotent_int
use k; rw [← le_bot_iff] at h ⊢
exact le_trans (LieModule.derivedSeries_le_lowerCentralSeries ℤ L k) h