A246376 Permutation of natural numbers: a(1) = 1, a(2n) = 2 * a(n), a(2n-1) = 1 + (2 * a(A064989(2n-1)-1)).

1, 2, 3, 4, 5, 6, 9, 8, 7, 10, 13, 12, 21, 18, 11, 16, 25, 14, 33, 20, 15, 26, 29, 24, 17, 42, 19, 36, 53, 22, 73, 32, 43, 50, 37, 28, 45, 66, 31, 40, 57, 30, 81, 52, 27, 58, 61, 48, 49, 34, 35, 84, 117, 38, 41, 72, 87, 106, 169, 44, 213, 146, 67, 64, 65, 86, 89, 100, 91, 74, 173, 56, 149, 90, 51, 132, 101, 62, 113, 80, 23

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

Index entries for sequences that are permutations of the natural numbers

Formula

a(1) = 1, a(2n) = 2 * a(n), a(2n-1) = 1 + (2 * a(A064989(2n-1)-1)).

As a composition of related permutations:

a(n) = A246377(A246380(n)).

Other identities. For all n >= 1 the following holds:

A000035(a(n)) = A000035(n). [Like A005940 & A005941, this also preserves the parity].

Prog

(Scheme, with memoizing definec-macro)
(definec (A246376 n) (cond ((<= n 1) n) ((even? n) (* 2 (A246376 (/ n 2)))) (else (+ 1 (* 2 (A246376 (- (A064989 n) 1)))))))

Crossrefs

Inverse: A246375.

Similar or related permutations: A005940, A005941, A064216, A243071, A245605, A246377, A246380.

Cf. A000035, A064989.

Sequence in context: A353591 A269838 A371985 * A269866 A246375 A269865

Adjacent sequences: A246373 A246374 A246375 * A246377 A246378 A246379

Keyword

nonn

Author

Antti Karttunen, Aug 27 2014

Status

approved