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A179039 Emirps with a single 7 as the only prime digit. 1
17, 71, 79, 97, 107, 167, 179, 701, 709, 761, 769, 907, 967, 971, 1097, 1471, 1487, 1741, 1789, 1847, 1867, 1879, 1979, 7481, 7649, 7681, 7699, 7841, 7901, 7949, 9467, 9479, 9497, 9679, 9749, 9769, 9781, 9791, 9871, 9967, 10007, 10067, 10079, 10487 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
emirpQ[n_] := Module[{idn=IntegerDigits[n], ridn}, ridn=Reverse[idn]; idn != ridn && PrimeQ[FromDigits[ridn]]]; only7Q[n_] := DigitCount[n, 10, 7] == 1 && Total[DigitCount[n, 10, {2, 3, 5}]] == 0; Select[Select[Prime[Range[1500]], emirpQ], only7Q] (* Harvey P. Dale, Jan 06 2011 *)
CROSSREFS
Sequence in context: A183943 A180532 A179038 * A152295 A039407 A043230
KEYWORD
base,nonn
AUTHOR
Lekraj Beedassy, Jun 25 2010
EXTENSIONS
Terms confirmed by Ray Chandler, Jul 13 2010
Definition clarified by Harvey P. Dale, Jan 06 2011
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)