A269863 Permutation of natural numbers: a(1) = 1, a(A269360(n)) = 2*a(n), a(A250469(1+n)) = 1 + 2*a(n).

1, 2, 3, 4, 5, 6, 9, 10, 7, 8, 13, 18, 17, 26, 11, 12, 37, 34, 25, 74, 19, 20, 69, 50, 21, 14, 15, 16, 41, 138, 33, 82, 27, 36, 53, 22, 277, 66, 35, 52, 45, 554, 105, 90, 23, 24, 1109, 210, 101, 42, 75, 68, 49, 2218, 149, 38, 51, 148, 137, 98, 297, 274, 39, 40, 29, 30, 197, 594, 139, 100, 61, 394, 201, 122, 43, 28, 73, 106, 789, 402, 31, 32

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, after which for even n, a(n) = 2*a(A268674(n-1)), for odd n, a(n) = 1 + 2*a(A268674(n)-1).

Prog

(Scheme, with memoization-macro definec)
(definec (A269863 n) (cond ((= 1 n) 1) ((even? n) (* 2 (A269863 (A268674 (- n 1))))) (else (+ 1 (* 2 (A269863 (+ -1 (A268674 n))))))))

Crossrefs

Inverse: A269864.

Cf. A250469, A268674, A269360.

Differs from similarly constructed A245605 for the first time at n=21, where a(21)=19, instead of 15.

Sequence in context: A023841 A340553 A245605 * A297165 A245606 A269864

Adjacent sequences: A269860 A269861 A269862 * A269864 A269865 A269866

Keyword

nonn

Author

Antti Karttunen, Mar 13 2016

Status

approved