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Semiprimes associated with A227942.
2

%I #11 Oct 06 2013 14:02:31

%S 9,10,14,15,25,35,58,62,82,94,39,57,93,65,85,95,91,106,122,142,158,

%T 166,194,141,159,177,183,201,219,237,267,291,205,235,295,305,335,365,

%U 395,415,445,203,259,329,371,413,497,143,319,341,473,583,671,869,913,979

%N Semiprimes associated with A227942.

%H Charles R Greathouse IV, <a href="/A227943/b227943.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) issemi(n)=bigomega(n)==2

%o do(lim)=my(v=List(), t); forprime(q=2, sqrtint(lim\10), forprime(p=2, min(sqrtint(lim\q), q), t=eval(Str(p, p*q, q)); if(t>lim, next(2)); if(issemi(t), listput(v, [t, p*q])))); apply(u->u[2], vecsort(Vec(v), 1)) \\ _Charles R Greathouse IV_, Oct 04 2013

%Y Cf. A227942, A001358, A229480.

%K nonn,base

%O 1,1

%A _G. L. Honaker, Jr._, Oct 03 2013

%E More terms from _Farideh Firoozbakht_ Oct 04 2013