A269866 Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = 1 + 2*a(A268674(2n+1)-1).

1, 2, 3, 4, 5, 6, 9, 8, 7, 10, 13, 12, 21, 18, 11, 16, 25, 14, 33, 20, 19, 26, 29, 24, 17, 42, 15, 36, 53, 22, 73, 32, 27, 50, 37, 28, 45, 66, 43, 40, 57, 38, 81, 52, 23, 58, 77, 48, 49, 34, 51, 84, 117, 30, 41, 72, 67, 106, 169, 44, 213, 146, 39, 64, 85, 54, 89, 100, 59, 74, 109, 56, 149, 90, 35, 132, 101, 86, 113, 80, 31

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..8192

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(A268674(2n+1)-1).

Prog

(Scheme, with memoization-macro definec)
(definec (A269866 n) (cond ((<= n 1) n) ((even? n) (* 2 (A269866 (/ n 2)))) (else (+ 1 (* 2 (A269866 (- (A268674 n) 1)))))))

Crossrefs

Inverse: A269865.

Cf. A268674.

Related or similar permutations: A269867, A249813, A252756, A270196.

Differs from similarly constructed A246376 for the first time at n=21, where a(21) = 19, instead of 15.

Sequence in context: A269838 A371985 A246376 * A246375 A269865 A269387

Adjacent sequences: A269863 A269864 A269865 * A269867 A269868 A269869

Keyword

nonn

Author

Antti Karttunen, Mar 12 2016

Status

approved