a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n-1 <= 2^(p+1), with a(1) = 1, a(2) = 2 and a(3) = 4.

A049963

a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n-1 <= 2^(p+1), with a(1) = 1, a(2) = 2 and a(3) = 4.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =9a(4) =25a(5) =43a(6) =93a(7) =220a(8) =617a(9) =1016a(10) =2039a(11) =4112a(12) =8401a(13) =17598a(14) =38292a(15) =90070a(16) =252612a(17) =415156a(18) =830319a(19) =1660672a(20) =3321521a(21) =6643838a(22) =13290772a(23) =26595030a(24) =53262532a(25) =106850150a(26) =214945816a(27) =434874798a(28) =889700788a(29) =1859656696

External references