A076877 a(n) = A020330(n) / n.

3, 5, 5, 9, 9, 9, 9, 17, 17, 17, 17, 17, 17, 17, 17, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 65, 129, 129, 129, 129, 129, 129

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Ralf Stephan, Some divide-and-conquer sequences with (relatively) simple ordinary generating functions, 2004.

Ralf Stephan, Table of generating functions.

Formula

a(n) = 1 + 2^(1 + Log2(n)), with Log2 = A000523.

a(n) = 1 + 2*A053644(n).

a(n) = 1 + A062383(n).

Example

12 -> '1100' -> '1100'1100' = '11001100' -> 204 = A020330(12): a(12) = A020330(12)/12 = 204/12 = 17.

Mathematica

a[n_] := 1 + 2^Floor[Log2[n] + 1]; Array[a, 50] (* Amiram Eldar, Apr 07 2021 *)

Crossrefs

Cf. A000523, A020330, A053644, A062383.

Sequence in context: A087349 A212631 A090792 * A332775 A120841 A145282

Adjacent sequences: A076874 A076875 A076876 * A076878 A076879 A076880

Keyword

nonn

Author

Reinhard Zumkeller, Nov 25 2002

Status

approved