Uniqueness Condition marginal ±exp(-) (d+1)-regular tree at root d =A(》 t reg. tree 元d=fa(cd) lf(元d)川<1 arbitrary boundary configUniqueness Condition (d+1)-regular tree reg. tree t arbitrary boundary config marginal at root ± exp(-t) fd(x) = ￾ ￾￾x + 1 x + ￾ ￾d x ˆ d = fd(ˆxd) |f￾ d(ˆxd)| < 1