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.
%I A249812 #18 Nov 15 2014 16:49:13
%S A249812 1,2,3,4,5,8,7,6,9,16,11,32,13,10,15,64,17,128,19,14,21,256,23,12,25,
%T A249812 18,27,512,29,1024,31,22,33,20,35,2048,37,26,39,4096,41,8192,43,30,45,
%U A249812 16384,47,24,49,34,51,32768,53,28,55,38,57,65536,59,131072,61,42,63,36,65,262144,67,46,69,524288,71,1048576,73,50,75,40,77,2097152,79,54,81,4194304,83,44
%N A249812 Permutation of natural numbers: a(n) = A000079(A055396(n+1)-1) * ((2*A078898(n+1))-1).
%C A249812 In the essence, a(n) tells which number in the array A135764 is at the same position where n is in the array A249741, the sieve of Eratosthenes minus 1. As the topmost row in both arrays is A005408 (odd numbers), they are fixed, i.e., a(2n+1) = 2n+1 for all n.
%C A249812 Equally: a(n) tells which number in array A054582 is at the same position where n is in the array A114881, as they are the transposes of above two arrays.
%H A249812 Antti Karttunen, <a href="/A249812/b249812.txt">Table of n, a(n) for n = 1..1024</a>
%H A249812 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A249812 a(n) = A000079(A055396(n+1)-1) * ((2*A078898(n+1))-1).
%F A249812 As a composition of related permutations:
%F A249812 a(n) = A054582(A250252(n)-1).
%F A249812 a(n) = A135764(A249742(n)).
%F A249812 a(n) = A246675(A249816(n)).
%F A249812 Other identities. For all n >= 1 the following holds:
%F A249812 a(A006093(n)) = A000079(n-1).
%o A249812 (Scheme) (define (A249812 n) (* (A000079 (- (A055396 (+ 1 n)) 1)) (+ -1 (* 2 (A078898 (+ 1 n))))))
%Y A249812 Inverse: A249811.
%Y A249812 Cf. A000079, A005408, A006093, A055396, A078898.
%Y A249812 Similar or related permutations: A249813 ("deep variant"), A246675, A249816, A054582, A114881, A250252, A135764, A249741, A249742.
%Y A249812 Differs from A246675 for the first time at n=20, where a(20)=14, while A246675(20)=18.
%K A249812 nonn
%O A249812 1,2
%A A249812 _Antti Karttunen_, Nov 06 2014