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 A371215 #5 Mar 16 2024 15:21:39 %S A371215 0,1,3,5,7,9,11,2,13,15,17,19,21,23,25,27,29,31,12,33,35,37,4,39,41, %T A371215 43,45,47,49,51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,6,83,32, %U A371215 85,87,89,91,93,95,97,38,99,101,103,105,107,109,111,113,115 %N A371215 Inverse permutation to A371214. %H A371215 Rémy Sigrist, <a href="/A371215/a371215.gp.txt">PARI program</a> %H A371215 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %F A371215 a(n) <= 2*n. %e A371215 A371214(42) = 1824, so a(1824) = 42. %o A371215 (PARI) See Links section. %Y A371215 Cf. A371214. %K A371215 nonn %O A371215 0,3 %A A371215 _Rémy Sigrist_, Mar 15 2024