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%I #18 Apr 18 2018 02:38:46
%S 6,9,10,15,33,34,39,46,51,57,58,65,77,85,86,95,106,111,119,123,129,
%T 141,142,159,166,169,177,178,183,187,201,202,209,215,219,221,226,235,
%U 237,249,267
%N Evil semiprimes.
%C Products of two (not necessarily distinct) primes such that the product has an even number of 1's in its binary expansion. Non-evil semiprimes are odious (A000069).
%H Harvey P. Dale, <a href="/A130593/b130593.txt">Table of n, a(n) for n = 1..1000</a>
%H E. Fouvry, C. Mauduit, <a href="http://dx.doi.org/10.1007/BF01444238">Sommes des chiffres et nombres presque premiers</a>, (French) [Sums of digits and almost primes] Math. Ann. 305 (1996), no. 3, 571--599. MR1397437 (97k:11029).
%F A001358 INTERSECTION A001969.
%t Select[Range[300],PrimeOmega[#]==2&&EvenQ[DigitCount[#,2,1]]&] (* _Harvey P. Dale_, Nov 08 2011 *)
%o (PARI) list(lim)=my(v=List(), t); forprime(p=2, lim\2, forprime(q=2, min(p,lim\p), if(hammingweight(n=p*q)%2,,listput(v, n)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Mar 26 2013
%Y Cf. A000069, A001358, A001969.
%K easy,base,nonn
%O 1,1
%A _Jonathan Vos Post_, Jun 16 2007
%E Corrected (a(21)=129 added) by _Harvey P. Dale_, Nov 08 2011
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