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%I #6 Oct 04 2016 16:13:14
%S 37,5372,5387,5537,38722,38887,53872,388722,388887,537037,537222,
%T 538887,555372,3703887,3705372,3705387,3870372,3870537,3887037,
%U 5387037,5537037,37220537,37222222,38705372,38705537,38870372,38870537,53703887
%N Numbers n with property that 6n+1 is prime and uses only digits 2 and 3.
%C a*n)=(A153165(n)-1)/6.
%H Harvey P. Dale, <a href="/A153166/b153166.txt">Table of n, a(n) for n = 1..1000</a>
%t pd23Q[n_]:=Module[{c=6n+1},PrimeQ[c]&&Union[IntegerDigits[c]]=={2,3}]; Select[ Range[ 54000000],pd23Q] (* _Harvey P. Dale_, Feb 08 2013 *)
%t Table[Select[(#-1)/6&/@Select[FromDigits/@Tuples[{2,3},n],OddQ[#] && PrimeQ[ #]&],IntegerQ],{n,9}]//Flatten (* _Harvey P. Dale_, Oct 04 2016 *)
%Y A153165
%K nonn,base
%O 1,1
%A _Zak Seidov_, Dec 20 2008
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