. split at ratAddSuccess
  . simp at ratAddSuccess
  . split at ratAddSuccess
    . simp at ratAddSuccess
    . next performRatCheck_fold_success =>
      simp only [Bool.not_eq_false] at performRatCheck_fold_success
      rw [f'_def]
      exact performRatCheck_fold_success_entails_safe_insert f f_readyForRatAdd c pivot rupHints ratHints pivot_in_c
        ratHintsExhaustive_eq_true performRatCheck_fold_success
case isFalse.isFalse
n : Nat
f : DefaultFormula n
c : DefaultClause n
pivot : Literal (PosFin n)
rupHints : Array Nat
ratHints : Array (Nat × Array Nat)
f' : DefaultFormula n
f_readyForRatAdd : f.readyForRatAdd
pivot_in_c : pivot ∈ Clause.toList c
f'_def : f' = f.insert c
ratHintsExhaustive_eq_true : f.ratHintsExhaustive pivot ratHints = true
h✝¹ : ¬(f.insertRupUnits c.negate).snd = true
h✝ : ¬((f.insertRupUnits c.negate).fst.performRupCheck rupHints).2.2.snd = true
ratAddSuccess :
  (if ((f.insertRupUnits c.negate).fst.performRupCheck rupHints).2.2.fst = true then
      (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, false)
    else
      if
          (Array.foldl
                (fun x ratHint =>
                  if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint else (x.fst, false))
                (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints 0).snd =
            false then
        ((Array.foldl
              (fun x ratHint =>
                if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint else (x.fst, false))
              (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints 0).fst,
          false)
      else
        ({
                  clauses :=
                    (Array.foldl
                          (fun x ratHint =>
                            if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint else (x.fst, false))
                          (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints 0).1.clauses,
                  rupUnits :=
                    (Array.foldl
                          (fun x ratHint =>
                            if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint else (x.fst, false))
                          (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints 0).1.rupUnits,
                  ratUnits :=
                    (Array.foldl
                          (fun x ratHint =>
                            if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint else (x.fst, false))
                          (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints 0).1.ratUnits,
                  assignments :=
                    restoreAssignments
                      (Array.foldl
                            (fun x ratHint =>
                              if x.snd = true then x.fst.performRatCheck pivot.negateLiteral ratHint
                              else (x.fst, false))
                            (((f.insertRupUnits c.negate).fst.performRupCheck rupHints).fst, true) ratHints
                            0).1.assignments
                      ((f.insertRupUnits c.negate).fst.performRupCheck rupHints).2.fst }.clearRupUnits.insert
            c,
          true)) =
    (f', true)
⊢ equisat (PosFin n) f f'
no goals