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%I #9 Feb 01 2017 22:20:58
%S 12,28,45,52,63,75,76,99,117,147,148,153,165,172,175,207,245,268,273,
%T 279,316,325,333,345,369,385,388,399,412,423,435,436,475,477,507,508,
%U 549,561,595,603,651,652,657,665,715,747,759,772,775,777,795,833,845
%N 3-almost primes whose prime factors sum to a prime.
%H Charles R Greathouse IV, <a href="/A107707/b107707.txt">Table of n, a(n) for n = 1..10000</a>
%e a(5) = 63 = 3*3*7 because 3+3+7 = 13 is prime.
%t Select[Range[1000],PrimeOmega[#]==3&&PrimeQ[Total[ Times@@@ FactorInteger[ #]]]&] (* _Harvey P. Dale_, Nov 10 2011 *)
%o (PARI) list(lim)=my(v=List()); forprime(p=2,lim\4, forprime(q=2,min(p,lim\p\2), forprime(r=2,min(q,lim\p\q), if(isprime(p+q+r), listput(v,p*q*r))))); Set(v) \\ _Charles R Greathouse IV_, Feb 01 2017
%K easy,nonn
%O 1,1
%A _Giovanni Teofilatto_, Jun 10 2005
%E Corrected and extended by _Ray Chandler_, Jun 12 2005