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A153640
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Primes made up of a nonprime number of only nonprime digits.
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0
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1009, 1019, 1049, 1061, 1069, 1091, 1109, 1181, 1409, 1481, 1489, 1499, 1601, 1609, 1619, 1669, 1699, 1801, 1811, 1861, 1889, 1901, 1949, 1999, 4001, 4019, 4049, 4091, 4099, 4111, 4409, 4441, 4481, 4649, 4691, 4801, 4861, 4889, 4909, 4919, 4969, 4999, 6011
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OFFSET
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1,1
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COMMENTS
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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
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LINKS
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MATHEMATICA
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Select[FromDigits/@Tuples[{0, 1, 4, 6, 8, 9}, 4], IntegerLength[#]==4&&PrimeQ[#]&] (* Harvey P. Dale, Aug 24 2017 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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