∀ {n : ℕ} (derivedLits : Std.Sat.CNF.Clause (Std.Tactic.BVDecide.LRAT.Internal.PosFin n))
  (derivedLits_arr : Array (Std.Sat.Literal (Std.Tactic.BVDecide.LRAT.Internal.PosFin n))),
  derivedLits_arr = { toList := derivedLits } → ∀ (k : Fin derivedLits_arr.size), ↑k < List.length derivedLits