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Proof step 17 from proof bytes2int-diff (previous step)

bytes2int(bytes0) = bytes2int(bytes.butlast) * 256 + band(b2i(bytes.last), 255), # bytes0 = # bytes, ∀ bytes0, bytes1. # bytes1 < # bytes → # bytes0 = # bytes1 ∧ bytes2int(bytes0) = bytes2int(bytes1) → bytes0 = bytes1 ⊦ bytes0 = bytes, # bytes = 1, bytes = []

User applied rule insert rewrite lemma

And obtained the following new goals

Proof step 18:
⊦ 1 < # bytes → bytes2int(bytes) = bytes2int(bytes.butlast) * 256 + band(b2i(bytes.last), 255)
Proof step 19:
1 < # bytes0, bytes2int(bytes0.butlast) * 256 + band(b2i(bytes0.last), 255) = bytes2int(bytes.butlast) * 256 + band(b2i(bytes.last), 255), # bytes0 = # bytes, ∀ bytes0, bytes1. # bytes1 < # bytes → # bytes0 = # bytes1 ∧ bytes2int(bytes0) = bytes2int(bytes1) → bytes0 = bytes1 ⊦ bytes0 = bytes, # bytes = 1, bytes = []

Rule argument

name: bytes2int-rec-01 rotate: F subst: [bytes] → [bytes0]

Additional information

Used simplifier rules: ⊦ 1 < m ↔ ¬(m = 0 ∨ m = 1);% ⊦ # bytes = 0 ↔ bytes = [];% ⊦ # [] = 0; Used terms: bytes0