a(n)=a(n-1)+a(m), where m=2n-2-2^(p+1) and 2^p<n-1<=2^(p+1), for n >= 4.

Terms

a(0) =1a(1) =3a(2) =3a(3) =6a(4) =12a(5) =15a(6) =21a(7) =36a(8) =72a(9) =75a(10) =81a(11) =96a(12) =132a(13) =207a(14) =303a(15) =510a(16) =1020a(17) =1023a(18) =1029a(19) =1044a(20) =1080a(21) =1155a(22) =1251a(23) =1458a(24) =1968a(25) =2991a(26) =4035a(27) =5190a(28) =6648a(29) =9639