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%I #21 Mar 05 2024 11:26:23
%S 1440,2016,2400,3168,3744,4704,4860,4896,5472,5600,6624,6804,7840,
%T 8352,8800,8928,10400,10656,10692,11616,11808,12150,12384,12636,13536,
%U 13600,15200,15264,16224,16524,16992,17248,17568,18400,18468,19296,19360
%N Numbers p^5*q^2*r where p, q, r are 3 distinct primes.
%H T. D. Noe, <a href="/A179691/b179691.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>
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,2,5}; Select[Range[20000], f]
%o (PARI) list(lim)=my(v=List(),t1,t2);forprime(p=2, (lim\12)^(1/5), t1=p^5;forprime(q=2, sqrt(lim\t1), if(p==q, next);t2=t1*q^2;forprime(r=2, lim\t2, if(p==r||q==r, next);listput(v,t2*r)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jul 24 2011
%Y Part of the list A178739 .. A179696 (and A030514 .. A030629, A189982 .. A189990 etc, cf. A101296). - _M. F. Hasler_, Jul 17 2019
%Y Subsequence of A175746 (numbers with 36 divisors).
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 24 2010
%E Name improved by _M. F. Hasler_, Jul 17 2019
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