3 ms·I think grandparent meant 2^(2^n), not (2^2)^n.by cousin_it 12y agoI think grandparent meant 2^(2^n), not (2^2)^n.chengsun 12y agoEven so, O(4^n) != O(8^n); there is no constant k such that k * 4^n >= 8^n.