A246205 Permutation of natural numbers: a(1) = 1, a(A014580(n)) = A117968(a(n)), a(A091242(n)) = A117967(1+a(n)), where A117967 and A117968 give positive and negative parts of inverse of balanced ternary enumeration of integers, and A014580 resp. A091242 are the binary coded irreducible resp. reducible polynomials over GF(2).

1, 2, 7, 5, 3, 11, 23, 15, 4, 12, 22, 33, 6, 52, 17, 13, 35, 43, 25, 16, 137, 45, 53, 36, 58, 155, 29, 47, 462, 154, 66, 135, 37, 152, 426, 30, 8, 156, 1273, 428, 24, 148, 460, 41, 423, 1426, 71, 31, 9, 427, 4283, 1410, 34, 431, 75, 1274, 159, 1423, 21, 3707, 194, 99, 44, 10, 1412, 11115, 64, 3850, 38, 1404, 103, 4281, 26, 412, 3722, 49

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..10001

Index entries for sequences operating on GF(2)[X]-polynomials

Index entries for sequences that are permutations of the natural numbers

Formula

a(1) = 1, and for n > 1, if A091225(n) = 1 [i.e. n is in A014580], a(n) = A117968(a(A091226(n))), otherwise a(n) = A117967(1+a(A091245(n))).

As a composition of related permutations:

a(n) = A246207(A245701(n)).

a(n) = A246209(A246201(n)).

Prog

(Scheme, with memoization-macro definec)
(definec (A246205 n) (cond ((= 1 n) n) ((= 1 (A091225 n)) (A117968 (A246205 (A091226 n)))) (else (A117967 (+ 1 (A246205 (A091245 n)))))))

Crossrefs

Inverse: A246206.

Similar or related entanglement permutations: A246163, A245701, A246201, A246207, A246209.

Cf. A014580, A091225, A091226, A091242, A091245, A117967, A117968.

Sequence in context: A138344 A354633 A171037 * A340117 A160669 A301816

Adjacent sequences: A246202 A246203 A246204 * A246206 A246207 A246208

Keyword

nonn

Author

Antti Karttunen, Aug 19 2014

Status

approved