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A179672 Products of the 6th power of a prime and 2 distinct primes (p^6*q*r). 8

%I

%S 960,1344,2112,2240,2496,3264,3520,3648,4160,4416,4928,5440,5568,5824,

%T 5952,6080,7104,7290,7360,7616,7872,8256,8512,9024,9152,9280,9920,

%U 10176,10206,10304,11328,11712,11840,11968,12864,12992,13120,13376,13632

%N Products of the 6th power of a prime and 2 distinct primes (p^6*q*r).

%H T. D. Noe, <a href="/A179672/b179672.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>

%p op(select(n->nops(factorset(n))=3 and sort([seq(op(2,a),a=ifactors(n)[2])])=[1,1,6],[$1..13632])); # _Paolo P. Lava_, Jul 18 2019

%t f[n_]:=Sort[Last/@FactorInteger[n]]=={1,1,6}; Select[Range[20000], f]

%o (PARI) list(lim)=my(v=List(),t1,t2);forprime(p=2, (lim\6)^(1/6), t1=p^6;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 20 2011

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Jul 23 2010

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Last modified February 25 14:40 EST 2021. Contains 341609 sequences. (Running on oeis4.)