A072650 Starting from the right (the least significant end) rewrite 0 to 0 and x1 to 1 in the binary expansion of n.

0, 1, 2, 1, 4, 3, 2, 3, 8, 5, 6, 5, 4, 3, 6, 3, 16, 9, 10, 9, 12, 7, 10, 7, 8, 5, 6, 5, 12, 7, 6, 7, 32, 17, 18, 17, 20, 11, 18, 11, 24, 13, 14, 13, 20, 11, 14, 11, 16, 9, 10, 9, 12, 7, 10, 7, 24, 13, 14, 13, 12, 7, 14, 7, 64, 33, 34, 33, 36, 19, 34, 19, 40, 21, 22, 21, 36, 19, 22, 19

Offset

0,3

Links

Table of n, a(n) for n=0..79.

Example

I.e. 23 is 10111 in binary, which after rewriting is 111, thus a(23) = 7, while 38 is 100110 in binary, which after the rewriting is 10010, i.e. a(38) = 18.

Prog

(MIT Scheme) (define (A072650 n) (let loop ((n n) (s 0) (i 0)) (cond ((zero? n) s) ((even? n) (loop (floor->exact (/ n 2)) s (1+ i))) (else (loop (floor->exact (/ n 4)) (+ s (expt 2 i)) (1+ i))))))

Crossrefs

Cf. A048679(n) = A072650(A003714(n)).

Sequence in context: A106407 A023141 A283324 * A082497 A242364 A065620

Adjacent sequences: A072647 A072648 A072649 * A072651 A072652 A072653

Keyword

nonn

Author

Antti Karttunen, Jun 02 2002

Status

approved