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A269867 Self-inverse permutation of natural numbers: a(1) = 1, for even n, a(n) = A250469(1+a(n/2)), for odd n, a(n) = 2*a(A268674(n)-1). 6

%I #6 Mar 15 2016 00:16:42

%S 1,3,2,9,6,5,18,27,4,11,10,15,22,23,12,81,30,7,162,33,36,13,14,45,54,

%T 29,8,69,26,17,138,243,20,37,46,21,34,167,44,99,42,41,198,39,24,35,82,

%U 135,90,91,60,87,70,25,66,207,324,65,174,51,130,149,72,729,58,55,102,111,28,53,110,63,106,77,108,501,74,115,126,297,16,47

%N Self-inverse permutation of natural numbers: a(1) = 1, for even n, a(n) = A250469(1+a(n/2)), for odd n, a(n) = 2*a(A268674(n)-1).

%H Antti Karttunen, <a href="/A269867/b269867.txt">Table of n, a(n) for n = 1..3165</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) = A250469(1+a(n)), a(2n+1) = 2*a(A268674(2n+1)-1).

%o (Scheme, with memoization-macro definec)

%o (definec (A269867 n) (cond ((<= n 1) n) ((even? n) (A250469 (+ 1 (A269867 (/ n 2))))) (else (* 2 (A269867 (- (A268674 n) 1))))))

%Y Cf. A250469, A268674.

%Y Similar permutations: A269865, A269866, A270197.

%K nonn

%O 1,2

%A _Antti Karttunen_, Mar 12 2016

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Last modified April 25 13:01 EDT 2024. Contains 371969 sequences. (Running on oeis4.)