[Imprint][Data Privacy Statement][E-Mail]

View long theorem info. View the proof. Back to main index. View the specification. View theorem base summary, View theorem base listing, the used properties by spec, the dependency list, the symbol table,

Proof step 12 from proof cast-mod-pos-low (previous step)

i→n(i) ≤ # int2bits(j), j % 2 ^ i < 2 ^ (i - 1), 0 < i, 0 ≤ j, 2 ^ (i - 1) ≤ j, j % 2 ^ i < j, 0 ≤ 2 ^ (i - 1) + j ⊦ bits2int(lastn(i→n(i), int2bits(j))) = j % 2 ^ i

User applied rule insert rewrite lemma

And obtained the following new goals

Proof step 13:
⊦ 2 ^ i ≤ j ∧ 0 < i → int2bits(j) = int2bits(j / 2 ^ i) + fillsgn(i→n(i + 1), int2bits(j % 2 ^ i)).rest
Proof step 14:
¬(2 ^ i ≤ j ∧ 0 < i), i→n(i) ≤ # int2bits(j), j % 2 ^ i < 2 ^ (i - 1), 0 < i, 0 ≤ j, 2 ^ (i - 1) ≤ j, j % 2 ^ i < j, 0 ≤ 2 ^ (i - 1) + j ⊦ bits2int(lastn(i→n(i), int2bits(j))) = j % 2 ^ i
Proof step 17:
2 ^ i ≤ j ∧ 0 < i, i→n(i) ≤ #(int2bits(j / 2 ^ i) + fillsgn(i→n(i + 1), int2bits(j % 2 ^ i)).rest), j % 2 ^ i < 2 ^ (i - 1), 0 < i, 0 ≤ j, 2 ^ (i - 1) ≤ j, j % 2 ^ i < j, 0 ≤ 2 ^ (i - 1) + j ⊦ bits2int(lastn(i→n(i), int2bits(j / 2 ^ i) + fillsgn(i→n(i + 1), int2bits(j % 2 ^ i)).rest)) = j % 2 ^ i

Rule argument

seq: ⊦ 2 ^ i ≤ j ∧ 0 < i → int2bits(j) = int2bits(j / 2 ^ i) + fillsgn(i→n(i + 1), int2bits(j % 2 ^ i)).rest subst: [i, j] → [i, j] rotate: F spec: int2bits inst: name: int2bits-rec-2pot-pos

Additional information

Used terms: i, j