This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A112392 #13 May 25 2020 20:52:27 %S A112392 16,25,64,100,169,256,361,400,529,625,676,784,961,1156,1444,2116,2209, %T A112392 3136,3721,3844,4096,4489,5041,5929,7744,7921,8281,9604,10000,10201, %U A112392 11236,11449,11881,12100,13456,14641,16129,16384,17161,18496,20164 %N A112392 Squares of the form 3*k - 2 where k is a semiprime. %C A112392 Even terms are 6*p-2 for p in A245045. - _Robert Israel_, May 25 2020 %H A112392 Robert Israel, <a href="/A112392/b112392.txt">Table of n, a(n) for n = 1..1000</a> %p A112392 select(issqr, map(t -> 3*t-2, select(t -> numtheory:-bigomega(t)=2,[$1..10000]))); # _Robert Israel_, May 25 2020 %t A112392 Select[3#-2&/@Select[Range[7000],PrimeOmega[#]==2&],IntegerQ[ Sqrt[#]]&] (* _Harvey P. Dale_, Jun 22 2011 *) %o A112392 (PARI) for(i=1,15000,if(bigomega(i)==2&&issquare(3*i-2),print1(3*i-2,","))) (Herrgesell) %Y A112392 Cf. A001358, A112393, A245045. %K A112392 nonn %O A112392 1,1 %A A112392 _Giovanni Teofilatto_, Dec 05 2005 %E A112392 More terms from Lambert Herrgesell (zero815(AT)googlemail.com), Dec 12 2005