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%I #14 Jun 26 2022 05:52:35
%S 64,256,576,729,1024,1296,1600,2304,2916,3136,4096,5184,6400,6561,
%T 7744,9216,10000,10816,11664,12544,14400,15625,16384,18225,18496,
%U 20736,23104,25600,26244,28224,30976,32400,33856,35721,36864,38416,40000,43264,46656,50176
%N Squares divisible by more than one cube > 1.
%H Hugo Pfoertner, <a href="/A321070/b321070.txt">Table of n, a(n) for n = 1..10000</a>
%F From _Amiram Eldar_, Jun 25 2022: (Start)
%F Equals A000290 \ (union of A062503 and A320965).
%F Sum_{n>=1} 1/a(n) = Pi^2/6 - (15/Pi^2) * (1 + Sum_{k>=2} (-1)^k * P(2*k)) = 0.029082273527998239268... . (End)
%e a(1) = 64 because 16^2 is divisible by 2^3 and by 4^3.
%t Select[Range[225]^2, Max[(e = FactorInteger[#][[;; , 2]])] > 4 || (Length[e] > 1 && Sort[e, Greater][[2]] > 2) &] (* _Amiram Eldar_, Jun 25 2022 *)
%o (PARI) iscubes(n) = {my(nb = 0); fordiv(n, d, if ((d>1) && ispower(d, 3), nb++; if (nb > 1, return(1))););}
%o isok(n) = issquare(n) && iscubes(n); \\ _Michel Marcus_, Oct 27 2018
%Y Cf. A000290, A000578, A062503, A062320, A216427, A320965.
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Oct 27 2018
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