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 A276622 #5 Sep 12 2016 17:03:16 %S A276622 0,1,3,2,8,7,6,5,4,20,19,18,17,16,15,14,13,12,11,10,9,49,48,47,46,45, %T A276622 44,43,42,41,40,39,38,37,36,35,34,33,32,31,30,29,28,27,26,25,24,23,22, %U A276622 21,123,122,121,120,119,118,117,116,115,114,113,112,111,110,109,108,107,106,105,104,103,102,101,100,99,98,97,96 %N A276622 Simple self-inverse permutation of natural numbers: after a(0)=0, list each block of A261234(n) numbers in reverse order, from A261232(n) to A261233(1+n). %C A276622 Maps between A276623 and A276624. %H A276622 Antti Karttunen, <a href="/A276622/b276622.txt">Table of n, a(n) for n = 0..6250</a> %H A276622 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A276622 a(0) = 0; for n >= 1, a(n) = A261232(A276621(n)-1) + A261232(A276621(n)) - n - 1. %o A276622 (Scheme) (define (A276622 n) (if (zero? n) n (+ (A261232 (+ -1 (A276621 n))) (- (A261232 (A276621 n)) n 1)))) %Y A276622 Cf. A261232, A276621, A276623, A276624. %K A276622 nonn,base %O A276622 0,3 %A A276622 _Antti Karttunen_, Sep 11 2016