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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
 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, 29, 8, 69, 26, 17, 138, 243, 20, 37, 46, 21, 34, 167, 44, 99, 42, 41, 198, 39, 24, 35, 82, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..3165 FORMULA a(1) = 1, a(2n) = A250469(1+a(n)), a(2n+1) = 2*a(A268674(2n+1)-1). PROG (Scheme, with memoization-macro definec) (definec (A269867 n) (cond ((<= n 1) n) ((even? n) (A250469 (+ 1 (A269867 (/ n 2))))) (else (* 2 (A269867 (- (A268674 n) 1)))))) CROSSREFS Cf. A250469, A268674. Similar permutations: A269865, A269866, A270197. Sequence in context: A175840 A125152 A229119 * A244319 A269359 A270199 Adjacent sequences:  A269864 A269865 A269866 * A269868 A269869 A269870 KEYWORD nonn AUTHOR Antti Karttunen, Mar 12 2016 STATUS approved

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Last modified January 22 08:40 EST 2021. Contains 340360 sequences. (Running on oeis4.)