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Emirps whose only prime digits are 3's.
2

%I #6 Nov 30 2012 17:52:46

%S 13,31,113,311,389,983,1031,1033,1103,1193,1301,1381,1399,1439,1831,

%T 1913,1933,3011,3019,3049,3083,3089,3109,3163,3169,3191,3301,3319,

%U 3343,3389,3391,3433,3463,3469,3613,3643,3803,3889,3911,9013,9103,9133,9341

%N Emirps whose only prime digits are 3's.

%H Harvey P. Dale, <a href="/A179034/b179034.txt">Table of n, a(n) for n = 1..1000</a>

%t em3Q[n_]:=Module[{idn=IntegerDigits[n],ridn},ridn=Reverse[idn]; idn!= ridn&&PrimeQ[FromDigits[ridn] && Count[idn,2] == Count[idn,5] == Count[idn,7] == 0&&Count[idn,3]>0]]; Select[Prime[Range[1200]],em3Q] (* _Harvey P. Dale_, Nov 30 2012 *)

%Y Cf. A006567, A179035.

%K base,nonn

%O 1,1

%A _Lekraj Beedassy_, Jun 25 2010

%E Corrected by _Ray Chandler_, Jul 13 2010