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 A306856 #7 Mar 16 2019 13:24:14 %S A306856 1,197,3,13,9,53,7,49,5,43,11,25,15,45,17,183,185,47,187,31,21,51,189, %T A306856 34,191,55,19,27,193,28,195,57,23,59,33,29,199,61,71,20,201,30,203,39, %U A306856 35,63,205,73,207,65,75,37,209,32,41,18,77,67,211,46,213,69 %N A306856 Inverse permutation to A306854. %H A306856 Rémy Sigrist, <a href="/A306856/a306856.gp.txt">PARI program for A306856</a> %H A306856 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %e A306856 A306854(197) = 2, hence a(2) = 197. %o A306856 (PARI) See Links section. %Y A306856 Cf. A306854. %K A306856 nonn %O A306856 1,2 %A A306856 _Rémy Sigrist_, Mar 13 2019