English
For the derived series of R,L on M, every term is contained in the corresponding lower central series term on the same module: derived_k ≤ lcs_k.
Русский
Производная серия удовлетворяет: derived_k ≤ lcs_k.
LaTeX
$$$derivedSeries(R,L,M,k) \\le lcs(R,L,M,k)$$$
Lean4
theorem derivedSeries_le_lowerCentralSeries (k : ℕ) : derivedSeries R L k ≤ lowerCentralSeries R L L k := by
induction k with
| zero => rw [derivedSeries_def, derivedSeriesOfIdeal_zero, lowerCentralSeries_zero]
| succ k h =>
have h' : derivedSeries R L k ≤ ⊤ := by simp only [le_top]
rw [derivedSeries_def, derivedSeriesOfIdeal_succ, lowerCentralSeries_succ]
exact LieSubmodule.mono_lie h' h