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%I #6 Oct 19 2015 11:59:55
%S 12,18,20,28,44,45,48,50,52,60,63,68,72,75,76,80,84,90,92,98,99,108,
%T 112,116,117,120,124,126,132,140,147,148,150,153,156,162,164,168,171,
%U 172,175,176,180,188,192,198,200,204,207,208,212,220,228,234,236,242
%N Composite numbers with coprime numbers of prime factors with and without repetition.
%C A001221(a(n))>1 and GreatestCommonDivisor(A001221(a(n)), A001222(a(n)))=1;
%C a(n)=A070011(n) for n<228, but A070011(228)=840=7*5*3*2^3 with omega=4 and bigOmega=6, as GCD(4,6)=2>1 840 is not a term.
%H Charles R Greathouse IV, <a href="/A084679/b084679.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) is(n)=my(f=factor(n)[,2]); #f>1 && gcd(vecsum(f),#f)==1 \\ _Charles R Greathouse IV_, Oct 19 2015
%Y Different from A070011.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jun 28 2003
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