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Proof step 83 from proof gcd-rec-sub-03 (previous step)

i0 < i, 0 < i, i0 < 0 ⊦ abs(i0) < abs(i), i0 = 0, i = 0, gcd(abs(i), abs(i0) - abs(i)) = gcd(abs(i0) - abs(i), abs(i0))

User applied rule insert rewrite lemma

And obtained the following new goals

Rule argument

spec: int-gcd inst: name: gcd-rec-sub-02 seq: ⊦ 0 < i ∧ i < j → gcd(i, j) = gcd(j, j - i) subst: [j, i] → [abs(i0), abs(i0) - abs(i)] flags: rewrite, current

Additional information

Used simplifier rules: gcd-neg: ⊦ gcd(~ i, j) = gcd(i, j);%gcd-com: ⊦ gcd(i, j) = gcd(j, i);%gcd-zero-03: ⊦ i ≠ 0 → gcd(i, 0) = abs(i);%abs-16: ⊦ 0 < j → abs(j) = j; from specification int-abs%abs-08: ⊦ i < 0 → abs(i) = ~ i; from specification int-abs%subsub: ⊦ ~ i - j = ~(i + j); from specification int-abs%neg-13: ⊦ ~ i < j ↔ 0 < j + i; from specification int-abs%lels: ⊦ ¬ i < j ↔ j ≤ i; from specification int-abs%neg: ⊦ 0 < ~ i ↔ i < 0; from specification int-abs%neg-01: ⊦ ~ j < ~ i ↔ i < j; from specification int-abs%forward-le-04: ⊦ j ≤ i ∧ i ≤ 0 → j ≤ 0; (forward) from specification int-abs%lep-01: ⊦ i + j ≤ i ↔ j ≤ 0; from specification int-abs%lels-02: ⊦ i ≠ j → (i ≤ j ↔ i < j); from specification int-abs%ls-01: ⊦ i < j → ¬ j < i; from specification int-basic1%add-a: ⊦ i + j + i0 = (i + j) + i0; from specification int-basic2%add-c: ⊦ i + j = j + i; from specification int-basic2%anti: ⊦ i ≤ j → (j ≤ i ↔ i = j); from specification int-abs%negeq: ⊦ ~ i = j ↔ i + j = 0; from specification int-abs Used terms: abs(i0), abs(i0) - abs(i)