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%I #7 Jul 30 2015 18:11:09
%S 3,14,15,16,17,18,22,24,25,27,28,40,41,42,50,51,52,60,61,70,71,72,80,
%T 81,82,102,104,105,107,108,112,114,115,117,118,120,121,123,125,126,
%U 128,132,140,141,144,145,146,147,148,150,151,152,154,156,157,158,162,164
%N Numbers n such that sum of the factorial of digits of n is semiprime.
%H K. D. Bajpai, <a href="/A242868/b242868.txt">Table of n, a(n) for n = 1..10000</a>
%e a(4) = 16: 1! + 6! = 1 + 720 = 721 = 7 * 103 which is semiprime.
%e a(9) = 25: 2! + 5! = 2 + 120 = 122 = 2 * 61 which is semiprime.
%p with(numtheory):A242868:= proc() local a; a:=add( i!,i = convert((n), base, 10))(n);if bigomega(a)=2 then RETURN (n);fi; end: seq(A242868 (), n=1..300);
%t Select[Range[200],PrimeOmega[Total[IntegerDigits[#]!]]==2&] (* _Harvey P. Dale_, Jul 30 2015 *)
%Y Cf. A001358, A061602, A165451.
%K nonn,base
%O 1,1
%A _K. D. Bajpai_, May 24 2014
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