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 A214195 #18 Sep 14 2015 09:23:45 %S A214195 1,30,42,60,66,70,78,84,90,102,105,110,114,120,126,130,132,138,140, %T A214195 150,154,156,165,168,170,174,180,182,186,190,195,198,204,220,222,228, %U A214195 230,231,234,238,240,246,252,255,258,260,264,266,270,273,276,280,282,285 %N A214195 Numbers with the number of distinct prime factors a multiple of 3. %C A214195 If GCD(a(n),a(m))=1, then a(n)*a(m) is also in this sequence. - _Enrique Pérez Herrero_, Nov 23 2013 %H A214195 Enrique Pérez Herrero, <a href="/A214195/b214195.txt">Table of n, a(n) for n = 1..5000</a> %F A214195 A010872(A001221(a(n))) = 0. %t A214195 Select[Range[1000],Mod[PrimeNu[#],3]==0&] %o A214195 (PARI) is(n)=omega(n)%3==0 \\ _Charles R Greathouse IV_, Sep 14 2015 %Y A214195 Subsequences include A033992, A067885, A007304 and A147573. %Y A214195 Cf. A145784, A030230, A030231. %K A214195 nonn %O A214195 1,2 %A A214195 _Enrique Pérez Herrero_, Jul 07 2012