(motive : Lean.Data.AC.Expr → Lean.Data.AC.Expr → Sort u_1) →
  (x x_1 : Lean.Data.AC.Expr) →
    ((a b : ℕ) → motive (Lean.Data.AC.Expr.var a) (Lean.Data.AC.Expr.var b)) →
      ((a a_1 b b_1 : Lean.Data.AC.Expr) → motive (a.op a_1) (b.op b_1)) →
        ((x x_2 : Lean.Data.AC.Expr) → motive x x_2) → motive x x_1