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 A194861 #8 Mar 18 2022 21:54:04 %S A194861 1,3,2,6,5,4,9,8,7,10,13,12,15,11,14,18,21,17,20,16,19,28,24,27,23,26, %T A194861 22,25,35,31,34,30,33,29,36,32,43,39,42,38,45,41,37,44,40,52,48,55,51, %U A194861 47,54,50,46,53,49,62,58,65,61,57,64,60,56,63,59,66,73,69,76 %N A194861 Inverse permutation to A194860; every positive integer occurs exactly once. %t A194861 (See A194860.) %Y A194861 Cf. A194860, A194859. %K A194861 nonn %O A194861 1,2 %A A194861 _Clark Kimberling_, Sep 04 2011