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 A069575 #24 Aug 04 2024 13:38:12
%S A069575 4,5,7,13,23,43,157,619
%N A069575 Numbers k >= 4 such that k contains the digit 0 in no base b with 2 < b < k.
%C A069575 Probably finite.
%C A069575 The next term (if it exists) is > 10000000. - Larry Reeves (larryr(AT)acm.org), Oct 12 2003
%C A069575 The next term (if it exists) is > 100000000. - _Michel Marcus_, Jul 14 2013
%C A069575 The next term (if it exists) is > 10^400. - _Nathan Fox_, Mar 09 2016
%C A069575 Every term in this sequence other than 4 is prime. - _Nathan Fox_, Mar 09 2016
%C A069575 No more terms through 10^5000. - _Jon E. Schoenfield_, Oct 13 2018
%o A069575 (PARI) isok(n) = {for (b=3, n-1, digs = digits(n, b); for (j=1, #digs, if (digs[j] == 0, return (0)););); return (1);} \\ _Michel Marcus_, Jul 14 2013
%K A069575 base,nonn,more
%O A069575 1,1
%A A069575 _Naohiro Nomoto_, Apr 18 2002
%E A069575 Corrected by Larry Reeves (larryr(AT)acm.org), Oct 12 2003