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%I #19 Oct 26 2019 17:33:25
%S 7560,11880,14040,16632,18360,19656,20520,21000,24840,25704,28728,
%T 30888,31320,33000,33480,34776,39000,39960,40392,41160,43848,44280,
%U 45144,46440,46872,47250,47736,50760,51000,53352,54648,55944,57000,57240,61992,63720,64584
%N Numbers with prime factorization p*q*r^3*s^3 (where p, q, r, s are distinct primes).
%C A050326(a(n)) = 11. - _Reinhard Zumkeller_, May 03 2013
%H T. D. Noe, <a href="/A190108/b190108.txt">Table of n, a(n) for n = 1..1000</a>
%H Will Nicholes, <a href="http://willnicholes.com/math/primesiglist.htm">Prime Signatures</a>
%H <a href="/index/Pri#prime_signature">Index to sequences related to prime signature</a>
%e From _Petros Hadjicostas_, Oct 26 2019: (Start)
%e a(1) = (2^3)*(3^3)*5*7 = 7560;
%e a(2) = (2^3)*(3^3)*5*11 = 11880;
%e a(3) = (2^3)*(3^3)*5*13 = 14040;
%e a(4) = (2^3)*(3^3)*7*11 = 16632.
%e (End)
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,3,3};Select[Range[150000],f]
%o (PARI) list(lim)=my(v=List(),t1,t2,t3); forprime(p=2,sqrtnint(lim\120, 3), t1=p^3; forprime(q=2,sqrtnint(lim\(6*t1), 3), if(q==p, next); t2=q^3*t1; forprime(r=2,lim\(2*t2), if(r==p || r==q, next); t3=r*t2; forprime(s=2,lim\t3, if(s==p || s==q || s==r, next); listput(v, t3*s))))); Set(v) \\ _Charles R Greathouse IV_, Aug 25 2016
%Y Cf. A179704, A190106, A190107.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 04 2011
%E Name edited by _Petros Hadjicostas_, Oct 26 2019
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