| ⊦ a ' + x + b ' = y + c ' + c ' + z ∧ a ≠ b ∧ ¬ a ∈ x ∧ ¬ b ∈ x → dups(x) |
a ' + x + b ' = y + c ' + c ' + z, a ∈ y, b ∈ y ∨ b = c ∨ b ∈ z ⊦ a = c, a = b, dups(x), b ∈ x, a ∈ x
Used simplifier rules: in-10: ⊦ ¬ a ∈ x → (a ∈ b ' + x ↔ a = b); from specification list%inapp-11: ⊦ x + y = z + a ' ∧ b ∈ x ∧ a ≠ b → b ∈ z; (forward) from specification list%inapp-02: ⊦ ¬ a ∈ y → (y + c ' + z = a ' + z0 ↔ y = [] ∧ c = a ∧ z = z0); from specification list%isin-01: ⊦ c ' + x + b ' = y + a ' + a ' + z ∧ a ≠ b → a ∈ x; from specification list%in-01: ⊦ a ≠ b → (a ∈ b ' + x ↔ a ∈ x); from specification list%in-rec: ⊦ a ∈ b ' + x ↔ ¬ ¬(a = b ∨ a ∈ x); from specification list%in-append: ⊦ a ∈ x + y ↔ ¬ ¬(a ∈ x ∨ a ∈ y); from specification list%in-15: ⊦ x + a ' = y → a ∈ y; (forward) from specification list%a: ⊦ (x + y) + z = x + y + z; from specification list%in-14: ⊦ a ' + x = y → a ∈ y; (forward) from specification list