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A269863 Permutation of natural numbers: a(1) = 1, a(A269360(n)) = 2*a(n), a(A250469(1+n)) = 1 + 2*a(n). 5

%I

%S 1,2,3,4,5,6,9,10,7,8,13,18,17,26,11,12,37,34,25,74,19,20,69,50,21,14,

%T 15,16,41,138,33,82,27,36,53,22,277,66,35,52,45,554,105,90,23,24,1109,

%U 210,101,42,75,68,49,2218,149,38,51,148,137,98,297,274,39,40,29,30,197,594,139,100,61,394,201,122,43,28,73,106,789,402,31,32

%N Permutation of natural numbers: a(1) = 1, a(A269360(n)) = 2*a(n), a(A250469(1+n)) = 1 + 2*a(n).

%H Antti Karttunen, <a href="/A269863/b269863.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, after which for even n, a(n) = 2*a(A268674(n-1)), for odd n, a(n) = 1 + 2*a(A268674(n)-1).

%o (Scheme, with memoization-macro definec)

%o (definec (A269863 n) (cond ((= 1 n) 1) ((even? n) (* 2 (A269863 (A268674 (- n 1))))) (else (+ 1 (* 2 (A269863 (+ -1 (A268674 n))))))))

%Y Inverse: A269864.

%Y Cf. A250469, A268674, A269360.

%Y Differs from similarly constructed A245605 for the first time at n=21, where a(21)=19, instead of 15.

%K nonn

%O 1,2

%A _Antti Karttunen_, Mar 13 2016

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Last modified January 19 16:16 EST 2021. Contains 340270 sequences. (Running on oeis4.)