A269391 - OEIS

%I #8 Mar 07 2016 12:29:52

%S 1,2,3,4,5,7,6,8,9,11,15,10,13,17,14,12,19,23,31,21,16,27,35,18,29,25,

%T 39,22,47,63,30,20,43,33,55,71,37,26,59,51,79,34,45,95,127,28,61,41,

%U 24,87,67,111,38,143,75,46,53,119,103,62,159,69,42,32,91,191,255,57,123,83,54,49,175,135,70,223,77,287,36

%N Permutation of natural numbers: a(1) = 1, a(A233271(1+n)) = 2*a(n), a(A269390(n)) = 1 + 2*a(n), where A233271 is the infinite trunk of inverted binary beanstalk and A269390 is its complement.

%H Antti Karttunen, <a href="/A269391/b269391.txt">Table of n, a(n) for n = 1..10000</a>

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

%F a(1) = 1, for n > 1, if A269381(n) - A269381(n-1) > 0 [when n is in A233271] a(n) = 2*a(A269381(n)-1), otherwise a(n) = 1 + 2*a(n-A269381(n)).

%F As a composition of other permutations:

%F a(n) = A269401(A269397(n)).

%o (Scheme, with memoization-macro definec)

%o (definec (A269391 n) (cond ((<= n 1) n) ((zero? (- (A269381 n) (A269381 (- n 1)))) (+ 1 (* 2 (A269391 (- n (A269381 n)))))) (else (* 2 (A269391 (+ -1 (A269381 n)))))))

%Y Inverse: A269392.

%Y Cf. A233271, A269381, A269390.

%Y Cf. also A260431.

%Y Similar or related permutations: A269397, A269401.

%K nonn,base

%O 1,2

%A _Antti Karttunen_, Mar 05 2016