| ∀ a, y. perm(ins≤(a, x0 + y), ins≤(a, x0) + y) ⊦ perm(ins≤(a, a0 ' + x0) + y, ins≤(a, (a0 ' + x0) + y)), perm(ins≤(a, (a0 ' + x0) + y), ins≤(a, a0 ' + x0) + y) |
a0 < a, ∀ a, y. perm(ins≤(a, x0 + y), ins≤(a, x0) + y) ⊦ perm(ins≤(a, (a0 ' + x0) + y), ins≤(a, a0 ' + x0) + y), perm(ins≤(a, a0 ' + x0) + y, ins≤(a, (a0 ' + x0) + y))
Used simplifier rules: ins-y: ⊦ ¬ b < a → ins≤(a, b ' + x) = a + b + x;% ⊦ a + x = a ' + x; (s)%a: ⊦ (x + y) + z = x + y + z; from specification list% ⊦ perm(x + y, x + z) ↔ perm(y, z); (s)% ⊦ perm(x, x); (s) Used formulas: a0 < a