cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A270195 Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A269369(1+a(n)).

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%I A270195 #6 Mar 15 2016 00:16:52
%S A270195 1,2,3,4,7,6,5,8,19,14,17,12,9,10,11,16,13,38,53,28,21,34,47,24,15,18,
%T A270195 23,20,39,22,29,32,61,26,35,76,57,106,155,56,103,42,59,68,123,94,137,
%U A270195 48,31,30,41,36,27,46,65,40,25,78,113,44,81,58,83,64,37,122,179,52,45,70,101,152,271,114,167,212,375,310,461,112,97
%N A270195 Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A269369(1+a(n)).
%C A270195 This sequence can be represented as a binary tree. When the parent contains n, the left hand child contains 2n, while the value of right hand child is obtained by applying A269369(1+n):
%C A270195                                     1
%C A270195                                     |
%C A270195                  ................../ \..................
%C A270195                 2                                       3
%C A270195       4......../ \........7                   6......../ \........5
%C A270195      / \                 / \                 / \                 / \
%C A270195     /   \               /   \               /   \               /   \
%C A270195    /     \             /     \             /     \             /     \
%C A270195   8       19         14       17         12       9          10       11
%C A270195 16 13   38  53     28  21   34  47     24  15   18 23      20  39   22  29
%C A270195 etc.
%H A270195 Antti Karttunen, <a href="/A270195/b270195.txt">Table of n, a(n) for n = 1..8191</a>
%H A270195 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A270195 a(1) = 1, a(2n) = 2*a(n), a(2n+1) = A269369(1+a(n)).
%o A270195 (Scheme, with memoization-macro definec)
%o A270195 (definec (A270195 n) (cond ((<= n 1) n) ((even? n) (* 2 (A270195 (/ n 2)))) (else (A269369 (+ 1 (A270195 (/ (- n 1) 2)))))))
%Y A270195 Inverse: A270196.
%Y A270195 Cf. A269369.
%Y A270195 Related or similar permutations: A269865, A269374, A269375, A270197.
%K A270195 nonn,tabf
%O A270195 1,2
%A A270195 _Antti Karttunen_, Mar 13 2016