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Proof step 122 from proof bytes2int-int2bytes-len-eq (previous step)

b2i(by0) < 0, 256 * b2i(by0) + band(b2i(by), 255) < ~128, ~256 < 256 * b2i(by0) + band(b2i(by), 255), 256 * b2i(by0) + band(b2i(by), 255) < 0, ∀ bytes0. # bytes0 < #((by0 + []) + by ') → true → # bytes0 = # int2bytes(bytes2int(bytes0)) → bytes0 = int2bytes(bytes2int(bytes0)) ⊦ i2b(~1) = by0

User applied rule cut formula

And obtained the following new goals

Proof step 123:
0 < 256 * (b2i(by0) + 1) + band(b2i(by), 255), b2i(by0) < 0, 256 * b2i(by0) + band(b2i(by), 255) < ~128, ~256 < 256 * b2i(by0) + band(b2i(by), 255), 256 * b2i(by0) + band(b2i(by), 255) < 0, ∀ bytes0. # bytes0 < #((by0 + []) + by ') → true → # bytes0 = # int2bytes(bytes2int(bytes0)) → bytes0 = int2bytes(bytes2int(bytes0)) ⊦ i2b(~1) = by0
Proof step 125:
b2i(by0) < 0, 256 * b2i(by0) + band(b2i(by), 255) < ~128, ~256 < 256 * b2i(by0) + band(b2i(by), 255), 256 * b2i(by0) + band(b2i(by), 255) < 0, ∀ bytes0. # bytes0 < #((by0 + []) + by ') → true → # bytes0 = # int2bytes(bytes2int(bytes0)) → bytes0 = int2bytes(bytes2int(bytes0)) ⊦ 0 < 256 * (b2i(by0) + 1) + band(b2i(by), 255), i2b(~1) = by0

Rule argument

fma: 0 < 256 * (b2i(by0) + 1) + band(b2i(by), 255)

Additional information

Used formulas: 0 < 256 * (b2i(by0) + 1) + band(b2i(by), 255)