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 A307278 #12 Jun 02 2025 15:21:51 %S A307278 0,1,21,38,66,518,845,12345679,172839506,445372913,1173450678278939, %T A307278 111222333444555666777889 %N A307278 Record values in A050782. %Y A307278 Cf. A020485, A050782, A307279. %K A307278 nonn,more %O A307278 1,3 %A A307278 _N. J. A. Sloane_, Apr 05 2019 %E A307278 a(11)-a(12) from _Giovanni Resta_, Oct 15 2022