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Proof step 44 from proof bytes2int-int2bytes-len-eq (previous step)

# bytes1 = # int2bytes((bytes2int(bytes1) * 256 + band(b2i(by), 255)) / 256 - 1), 256 ≤ abs(band(b2i(by), 255)), bytes2int(bytes1) < 0, bytes2int(bytes1) * 256 + band(b2i(by), 255) < ~256, bytes2int(bytes1) * 256 + band(b2i(by), 255) < 0, ∀ bytes0. # bytes0 < #(bytes1 + by ') → true → # bytes0 = # int2bytes(bytes2int(bytes0)) → bytes0 = int2bytes(bytes2int(bytes0)) ⊦ band(b2i(by), 255) % 256 = 0, (bytes2int(bytes1) * 256 + band(b2i(by), 255)) % 256 = 0, bytes2int(bytes1) * 256 + band(b2i(by), 255) = ~256, bytes1 = [], bytes1 + by ' = int2bytes((bytes2int(bytes1) * 256 + band(b2i(by), 255)) / 256 - 1) + int2bytes((bytes2int(bytes1) * 256 + band(b2i(by), 255)) % 256).last ', b2i(by) = 0

User applied rule insert rewrite lemma

And obtained the following new goals

Proof step 45:
⊦ ¬ j < 0 → abs(j) = j

Rule argument

seq: ⊦ ¬ j < 0 → abs(j) = j subst: [j] → [band(b2i(by), 255)] rotate: F spec: int-abs inst: name: Abs-pos

Additional information

Used simplifier rules: ⊦ 0 ≤ i → ¬ band(i, j) < 0;% ⊦ ¬ 256 ≤ band(i, 255);% ⊦ band(i, band(i0, j)) = band(band(i, i0), j);% ⊦ band(i, j) = band(j, i); Used terms: band(b2i(by), 255)