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A179038
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Emirps whose only prime digits are 7's.
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1
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17, 71, 79, 97, 107, 167, 179, 701, 709, 761, 769, 907, 967, 971, 1097, 1471, 1487, 1741, 1789, 1847, 1867, 1879, 1979, 7177, 7187, 7481, 7649, 7681, 7687, 7699, 7717, 7817, 7841, 7867, 7879, 7901, 7949, 9467, 9479, 9497, 9679, 9749, 9769, 9781, 9787
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..45.
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MATHEMATICA
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okQ[n_]:=Module[{idn=IntegerDigits[n], rev}, rev=Reverse[idn]; idn!=rev && Union[Select[idn, PrimeQ]]=={7}&&PrimeQ[FromDigits[rev]]]; Select[ Prime[ Range[1300]], okQ] (* Harvey P. Dale, Jul 18 2011 *)
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CROSSREFS
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Cf. A006567, A179039.
Sequence in context: A327495 A183943 A180532 * A179039 A152295 A039407
Adjacent sequences: A179035 A179036 A179037 * A179039 A179040 A179041
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KEYWORD
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base,nonn
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AUTHOR
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Lekraj Beedassy, Jun 25 2010
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EXTENSIONS
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Terms confirmed by Ray Chandler, Jul 13 2010
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STATUS
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approved
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