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A190293 Numbers with prime factorization pqr^2s^5. 3

%I

%S 10080,15840,16800,18720,22176,23520,24480,26208,26400,27360,31200,

%T 33120,34020,34272,38304,40800,41184,41760,44640,45600,46368,51744,

%U 53280,53460,53856,55200,58080,58464,59040,60192,61152,61600,61920,62496

%N Numbers with prime factorization pqr^2s^5.

%H T. D. Noe, <a href="/A190293/b190293.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>

%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,2,5};Select[Range[100000],f]

%o (PARI) list(lim)=my(v=List(),t1,t2,t3); forprime(p=2,sqrtnint(lim\60, 5), t1=p^5; forprime(q=2,sqrtint(lim\(6*t1)), if(q==p, next); t2=q^2*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. A162144, A190115, A190292.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, May 07 2011

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Last modified May 19 17:48 EDT 2019. Contains 323395 sequences. (Running on oeis4.)