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 A307630 #30 Nov 05 2023 17:41:05 %S A307630 1,3,5,27,47,99,53,137,177,1024,1374,2474,1386,3326,3662,5274,3738, %T A307630 6290,3756,8954,9374,12878,6680,9682,9850,10324,11010,14578,6704, %U A307630 78506,84626,106968,88474,127682,86802,143544,84658,160664,97850,274079,89480,326195 %N A307630 Index at which n first appears in A307720. %H A307630 Rémy Sigrist, <a href="/A307630/b307630.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..239 from Hans Havermann, terms 240..669 from Lars Blomberg) %H A307630 Rémy Sigrist, <a href="/A307630/a307630.png">Log-plot of first 5000 terms</a>. %H A307630 Rémy Sigrist, <a href="/A307630/a307630.txt">C++ program for A307630</a>. %o A307630 (C++) See Links section. %Y A307630 Cf. A307720, A307631, A307632, A307633, A307634, A307730, A307747. %K A307630 nonn %O A307630 1,2 %A A307630 _N. J. A. Sloane_, Apr 25 2019 %E A307630 More terms from _Hans Havermann_, Apr 25 2019