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%I #13 May 25 2020 20:52:27
%S 16,25,64,100,169,256,361,400,529,625,676,784,961,1156,1444,2116,2209,
%T 3136,3721,3844,4096,4489,5041,5929,7744,7921,8281,9604,10000,10201,
%U 11236,11449,11881,12100,13456,14641,16129,16384,17161,18496,20164
%N Squares of the form 3*k - 2 where k is a semiprime.
%C Even terms are 6*p-2 for p in A245045. - _Robert Israel_, May 25 2020
%H Robert Israel, <a href="/A112392/b112392.txt">Table of n, a(n) for n = 1..1000</a>
%p select(issqr, map(t -> 3*t-2, select(t -> numtheory:-bigomega(t)=2,[$1..10000]))); # _Robert Israel_, May 25 2020
%t Select[3#-2&/@Select[Range[7000],PrimeOmega[#]==2&],IntegerQ[ Sqrt[#]]&] (* _Harvey P. Dale_, Jun 22 2011 *)
%o (PARI) for(i=1,15000,if(bigomega(i)==2&&issquare(3*i-2),print1(3*i-2,","))) (Herrgesell)
%Y Cf. A001358, A112393, A245045.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Dec 05 2005
%E More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 12 2005
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