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Permutation of natural numbers: a(1) = 1, a(2n) = 2 * a(n), a(2n-1) = 1 + (2 * a(A064989(2n-1)-1)).
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%I #7 Sep 01 2014 11:47:07

%S 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,

%T 19,36,53,22,73,32,43,50,37,28,45,66,31,40,57,30,81,52,27,58,61,48,49,

%U 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

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

%H Antti Karttunen, <a href="/A246376/b246376.txt">Table of n, a(n) for n = 1..16384</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

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

%F As a composition of related permutations:

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

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

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

%o (Scheme, with memoizing definec-macro)

%o (definec (A246376 n) (cond ((<= n 1) n) ((even? n) (* 2 (A246376 (/ n 2)))) (else (+ 1 (* 2 (A246376 (- (A064989 n) 1)))))))

%Y Inverse: A246375.

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

%Y Cf. A000035, A064989.

%K nonn

%O 1,2

%A _Antti Karttunen_, Aug 27 2014