A179039 Emirps with a single 7 as the only prime digit.

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

Offset

1,1

Links

Table of n, a(n) for n=1..44.

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

Cf. A006567, A179038.

Sequence in context: A183943 A180532 A179038 * A152295 A039407 A043230

Adjacent sequences: A179036 A179037 A179038 * A179040 A179041 A179042

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