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%I #26 Jul 06 2020 02:40:52
%S 576,1600,2916,3136,7744,10816,18225,18496,23104,33856,35721,53824,
%T 61504,62500,87616,88209,107584,118336,123201,140625,141376,179776,
%U 210681,222784,238144,263169,287296,322624,341056,385641,399424,440896,470596
%N Numbers with prime factorization p^2*q^6.
%H T. D. Noe, <a href="/A189990/b189990.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>
%F Sum_{n>=1} 1/a(n) = P(2)*P(6) - P(8) = A085548 * A085966 - A085968 = 0.003658..., where P is the prime zeta function. - _Amiram Eldar_, Jul 06 2020
%t f[n_]:=Sort[Last/@FactorInteger[n]]=={2,6}; Select[Range[800000],f]
%o (PARI) list(lim)=my(v=List(),t);forprime(p=2, (lim\4)^(1/6), t=p^6;forprime(q=2, sqrt(lim\t), if(p==q, next);listput(v,t*q^2))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jul 24 2011
%Y Subsequence of A137484.
%Y Cf. A179645, A179664.
%Y Cf. A085548, A085966, A085968.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, May 03 2011
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