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%I #11 Nov 21 2013 12:50:05
%S 17,71,79,97,107,167,179,701,709,761,769,907,967,971,1097,1471,1487,
%T 1741,1789,1847,1867,1879,1979,7481,7649,7681,7699,7841,7901,7949,
%U 9467,9479,9497,9679,9749,9769,9781,9791,9871,9967,10007,10067,10079,10487
%N Emirps with a single 7 as the only prime digit.
%t 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 *)
%Y Cf. A006567, A179038.
%K base,nonn
%O 1,1
%A _Lekraj Beedassy_, Jun 25 2010
%E Terms confirmed by _Ray Chandler_, Jul 13 2010
%E Definition clarified by Harvey P. Dale, Jan 06 2011
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