∀ {n : ℕ} (f f_1 : Std.Tactic.BVDecide.LRAT.Internal.DefaultFormula n) (e_f : f = f_1)
  (fassignments_size : f.assignments.size = n)
  (assignments assignments_1 : Array Std.Tactic.BVDecide.LRAT.Internal.Assignment)
  (e_assignments : assignments = assignments_1) (assignments_size : assignments.size = n)
  (derivedLits derivedLits_1 : Std.Sat.CNF.Clause (Std.Tactic.BVDecide.LRAT.Internal.PosFin n)),
  derivedLits = derivedLits_1 →
    f.DerivedLitsInvariant fassignments_size assignments assignments_size derivedLits =
      f_1.DerivedLitsInvariant ⋯ assignments_1 ⋯ derivedLits_1