| ⊦ 0.r ≤ r0 ∧ 0.r ≤ r → r + r0 ≠ ~ 1.r + ~ 1.r |
r + r0 = ~ 1.r + ~ 1.r, 0.r ≤ r0, 0.r ≤ r ⊦
| r + r0 = ~ 1.r + ~ 1.r, 0.r ≤ r0, 0.r ≤ r ⊦ |
2.r + r + r0 = 0.r, ¬ r < 0.r, ¬ r0 < 0.r ⊦
Used simplifier rules: le-def: ⊦ r ≤ r0 ↔ ¬ r0 < r; add-comm: ⊦ r + r0 = r0 + r; from specification real-basic add-assoc: ⊦ (r + r0) + r1 = r + r0 + r1; from specification real-basic add-c: ⊦ i + j = j + i; from specification int-basic2 add-a: ⊦ i + j + i0 = (i + j) + i0; from specification int-basic2 ⊦ (* i).r + (* j).r = (i + j).r; (s) ⊦ r + 1.r = ~ 1.r ↔ r + 1.r + 1.r = 0.r; (s) ⊦ ~ r + r0 = r1 ↔ r0 = r1 + r; (as)
| 2.r + r + r0 = 0.r, ¬ r < 0.r, ¬ r0 < 0.r ⊦ |
2.r + r + r0 = 0.r, 2.r ≤ 2.r + r + r0, ¬ r < 0.r, ¬ r0 < 0.r ⊦
Used simplifier rules: le-def: ⊦ r ≤ r0 ↔ ¬ r0 < r; lf-02: ⊦ r < r0 ∧ r0 = r1 → r < r1; (forward) from specification real-basic lf-07: ⊦ ¬ r < r1 ∧ r0 < r1 → r0 < r; (forward) from specification real-basic ⊦ r + r0 < r + r1 ↔ r0 < r1; (s) ⊦ r < r + r0 ↔ 0.r < r0; (s) ⊦ i.r < j.r ↔ i < j; (s) ⊦ r + r0 < r0 ↔ r < 0.r; (s) add-assoc: ⊦ (r + r0) + r1 = r + r0 + r1; from specification real-basic add-comm: ⊦ r + r0 = r0 + r; from specification real-basic Used formulas: 2.r ≤ 2.r + r + r0
| 2.r + r + r0 = 0.r, 2.r ≤ 2.r + r + r0, ¬ r < 0.r, ¬ r0 < 0.r ⊦ |
Used simplifier rules: le-def: ⊦ r ≤ r0 ↔ ¬ r0 < r; ⊦ i.r < j.r ↔ i < j; (s)
The following image shows the proof tree of sequent calculus. The proved goal is at the bottom. You can click on the nodes to view additional rules. See here for details on colors in a proof tree.