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), starting with a(1) = 1, a(2) = 3, and a(3) = 2.
A049971
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), starting with a(1) = 1, a(2) = 3, and a(3) = 2.
Terms
- a(0) =1a(1) =3a(2) =2a(3) =9a(4) =24a(5) =42a(6) =90a(7) =213a(8) =597a(9) =984a(10) =1974a(11) =3981a(12) =8133a(13) =17037a(14) =37071a(15) =87198a(16) =244557a(17) =401919a(18) =803844a(19) =1607721a(20) =3215613a(21) =6431997a(22) =12866991a(23) =25747038a(24) =51564237a(25) =103443195a(26) =208092192a(27) =421008660a(28) =861332361a(29) =1800360879
External references
- oeis: A049971