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%I #6 Aug 24 2017 17:32:21
%S 1009,1019,1049,1061,1069,1091,1109,1181,1409,1481,1489,1499,1601,
%T 1609,1619,1669,1699,1801,1811,1861,1889,1901,1949,1999,4001,4019,
%U 4049,4091,4099,4111,4409,4441,4481,4649,4691,4801,4861,4889,4909,4919,4969,4999,6011
%N Primes made up of a nonprime number of only nonprime digits.
%C There are no one-digit terms, 106 four-digit terms, 2493 six-digit terms, 65989 eight-digit terms, and 350408 nine-digit terms. Of course, there are many more terms of greater-than-9-digit length. - _Harvey P. Dale_, Aug 24 2017
%t Select[FromDigits/@Tuples[{0,1,4,6,8,9},4],IntegerLength[#]==4&&PrimeQ[#]&] (* _Harvey P. Dale_, Aug 24 2017 *)
%Y A034844
%K nonn,base
%O 1,1
%A _Lekraj Beedassy_, Dec 29 2008
%E Corrected by _Harvey P. Dale_, Aug 24 2017
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