starts as 1, 3, 6, 7, 12, 14, 15, 24, 28, 30, 31, 48, 56, 60, 62, 63, 96, 112, 120, 124, 126, 127, Numbers of the form (2^k-1)*2^j for k>=1 and j>=0 Interesting(?) property: For all a(n)>1 the set (2^j)%a(n) consists only of the powers of two.