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 A236368 #16 Jan 16 2022 00:58:15 %S A236368 1,1,7,3367,281192547174175, %T A236368 1766847064778382532572997586311708102647654387270579226645978663441513375 %N A236368 a(n) = 4^(n!) - 3^(n!). %C A236368 a(6) has 434 digits. %F A236368 a(n) = 4^(n!) - 3^(n!) = A101407(n) - A100731(n). %e A236368 a(3) = 4^(3!) - 3^(3!) = 4^6 - 3^6 = 3367. %t A236368 4^#-3^#&/@(Range[0,5]!) (* _Harvey P. Dale_, Nov 26 2016 *) %o A236368 (PARI) a(n) = 4^(n!) - 3^(n!); \\ _Michel Marcus_, Jan 23 2014 %Y A236368 Cf. A175985, A203925. %Y A236368 Cf. A100731, A101407. %K A236368 nonn %O A236368 0,3 %A A236368 _Assoul Abdelkarim_, Jan 23 2014