If A,B are integers not both zero, abs(A²-2B²)>=1; hence |A+B*sqrt2|>=1/(|A|+2*|B|). Denominator is positive.
Method: native-order. Induction: none. Risk: routine.
This is a human-readable planning contract, not a parsed kernel formula or accepted proof.
Planned prerequisites and notation
Open this dependency coneChecked supporting leaves, not parent closure
The planning contract above remains open. Checked arithmetic DAG · Complete execution evidence.