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