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 A268817 #5 Feb 17 2016 17:22:26 %S A268817 0,1,6,4,3,9,2,7,12,22,5,11,24,13,10,8,15,45,14,19,48,21,18,16,23,25, %T A268817 30,28,27,17,26,31,20,94,29,35,96,37,34,32,39,41,46,44,43,33,42,47,36, %U A268817 49,54,52,51,57,50,55,60,38,53,59,40,61,58,56,63,189,62,67,192,69,66,64,71,73,78,76,75,65,74,79,68,81 %N A268817 Permutation of nonnegative integers: a(n) = A268717(A268717(n)). %H A268817 Antti Karttunen, <a href="/A268817/b268817.txt">Table of n, a(n) for n = 0..8191</a> %H A268817 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A268817 a(n) = A268717(A268717(n)). %o A268817 (Scheme) (define (A268817 n) (A268717 (A268717 n))) %Y A268817 Inverse: A268818. %Y A268817 Cf. A268717. %Y A268817 Cf. also A268821. %K A268817 nonn %O A268817 0,3 %A A268817 _Antti Karttunen_, Feb 14 2016