A269383 Permutation of natural numbers: a(1) = 1, a(n) = A000079(A260738(n+1)-1) * ((2 * a(A260739(n+1))) - 1).

1, 2, 3, 4, 5, 8, 7, 6, 9, 16, 15, 32, 13, 10, 11, 64, 17, 12, 31, 14, 29, 128, 63, 256, 25, 18, 19, 512, 21, 24, 127, 30, 33, 20, 23, 1024, 61, 26, 27, 2048, 57, 4096, 255, 22, 125, 8192, 511, 28, 49, 34, 35, 16384, 37, 48, 1023, 62, 41, 40, 47, 32768, 253, 58, 59, 36, 65, 65536, 39, 126, 45, 131072, 2047, 96, 121, 50, 51, 262144, 53, 60

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..1024

Index entries for sequences that are permutations of the natural numbers

Formula

a(1) = 1, a(n) = A000079(A260738(n+1)-1) * ((2 * a(A260739(n+1))) - 1).

Other identities. For all n >= 0:

A000035(a(n)) = A000035(n). [This permutation preserves the parity of n.]

Prog

(Scheme, with memoization-macro definec)
(definec (A269383 n) (cond ((<= n 1) n) (else (* (A000079 (- (A260738 (+ 1 n)) 1)) (+ -1 (* 2 (A269383 (A260739 (+ 1 n)))))))))

Crossrefs

Inverse: A269384.

Cf. A000035, A000079, A260738, A260739.

Cf. also A249813, A269373.

Differs from both A246683 and A249813 for the first time at n=18, which here a(18)=12, instead of 128.

Sequence in context: A252754 A246677 A156552 * A249813 A246683 A332816

Adjacent sequences: A269380 A269381 A269382 * A269384 A269385 A269386

Keyword

nonn

Author

Antti Karttunen, Mar 01 2016

Status

approved