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A179747 Numbers of the form p^8*q*r where p, q, and r are distinct primes. 3


%S 3840,5376,8448,8960,9984,13056,14080,14592,16640,17664,19712,21760,

%T 22272,23296,23808,24320,28416,29440,30464,31488,33024,34048,36096,

%U 36608,37120,39680,40704,41216,45312,46848,47360,47872,51456,51968,52480,53504,54528

%N Numbers of the form p^8*q*r where p, q, and r are distinct primes.

%H T. D. Noe, <a href="/A179747/b179747.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]]=={1,1,8};Select[Range[60000], f]

%o (PARI) list(lim)=my(v=List(),t1,t2);forprime(p=2, (lim\6)^(1/8), t1=p^8;forprime(q=2, lim\t1, if(p==q, next);t2=t1*q;forprime(r=q+1, lim\t2, if(p==r,next);listput(v,t2*r)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jul 24 2011

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jul 25 2010

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Last modified October 1 01:06 EDT 2022. Contains 357127 sequences. (Running on oeis4.)