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 A266643 #8 Jan 09 2016 16:08:01 %S A266643 0,1,2,3,4,7,6,5,8,9,10,19,12,11,22,21,16,25,18,13,20,15,14,27,24,73, %T A266643 58,23,28,39,30,37,64,57,46,17,36,67,26,55,40,31,66,49,76,51,54,65,48, %U A266643 41,50,75,44,163,34,29,56,77,78,61,60,53,74,45,32,59,42,43,68,81,70,33,72,35,82,63,52,71,38,47,80,69 %N A266643 Permutation of nonnegative integers: a(n) = A264965(3*n) / 3. %H A266643 Antti Karttunen, <a href="/A266643/b266643.txt">Table of n, a(n) for n = 0..10921</a> %H A266643 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A266643 a(n) = A264965(3*n) / 3. %F A266643 As a composition of related permutations: %F A266643 a(n) = A263273(A246200(n)). %o A266643 (Scheme, two alternatives) %o A266643 (define (A266643 n) (/ (A264965 (* 3 n)) 3)) %o A266643 (define (A266643 n) (A263273 (A246200 n))) %Y A266643 Inverse: A266644. %Y A266643 Cf. A246200, A263273, A264965, A265329, A265369, A266635, A266636, A266641, A266642. %K A266643 nonn,base %O A266643 0,3 %A A266643 _Antti Karttunen_, Jan 04 2016