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%I #8 Oct 19 2012 12:10:25
%S 22,25,33,35,55,57,77,235,237,253,323,327,335,355,377,527,533,535,537,
%T 553,573,723,737,753,755,2227,2253,2257,2323,2327,2335,2353,2533,2537,
%U 2573,2577,2722,2723,2733,2735,2757,2773,3223,3227,3233,3235,3273,3277
%N Semiprimes with prime digits (only digits 2,3,5,7 in semiprimes).
%C Complement of 108631 in the class of semiprimes.
%H Vincenzo Librandi, <a href="/A108632/b108632.txt">Table of n, a(n) for n = 1..1000</a>
%t fQ[n_]:=Plus@@Last/@FactorInteger[n]==2&&Union[{2, 3, 5, 7}, IntegerDigits[n]]=={2, 3, 5, 7};Select[Range[4000], fQ[ # ]&]
%t Select[FromDigits/@Flatten[Table[Tuples[{2,3,5,7},n],{n,2,4}],1],PrimeOmega[#]==2&] (* _Harvey P. Dale_, Oct 19 2012 *)
%Y Cf. A108631.
%K nonn,base
%O 1,1
%A _Zak Seidov_, Jun 13 2005
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