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%I #32 Sep 20 2018 05:11:22
%S 14,21,26,33,38,46,57,62,69,74,85,93,94,106,129,133,134,145,166,177,
%T 178,205,213,217,218,226,237,249,253,254,262,265,278,309,314,334,362,
%U 393,398,417,422,445,466,469,489,493,502,505,514,517,526,553,565,573,586
%N Nonsquare semiprimes with semiprime sum of factors.
%C Squares of primes are not included. - _Zak Seidov_, Sep 14 2018
%H Zak Seidov, <a href="/A108633/b108633.txt">Table of n, a(n) for n = 1..1000</a>
%e 21 = 3*7 and 3 + 7 = 10 = 2*5.
%t Select[Range[800], Plus@@Last/@FactorInteger[ # ]==Plus@@Last/@FactorInteger[(Plus@@First/@FactorInteger[ # ])]==2&]
%o (PARI) is(n) = if(bigomega(n)!=2, return(0), my(f=factor(n)[, 1]~); #f==2 && bigomega(sum(i=1, #f, f[i]))==2) \\ _Felix Fröhlich_, Sep 17 2018
%Y Cf. A001358 (semiprimes), A006881 (squarefree semiprimes).
%K nonn
%O 1,1
%A _Zak Seidov_, Jun 14 2005
%E Name clarified by _David A. Corneth_, Sep 17 2018
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