A049886 a(n)=a(1)+a(2)+...+a(n-1)-a(m), where m=n-1-2^p and 2^p<n-1<=2^(p+1).

1, 1, 1, 2, 4, 8, 16, 32, 63, 127, 254, 508, 1015, 2028, 4052, 8096, 16176, 32383, 64766, 129532, 259063, 518124, 1036244, 2072480, 4144944, 8289857, 16579650, 33159173, 66318092, 132635677, 265270341, 530538658, 1061073272, 2122154639