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%I #24 Sep 24 2023 09:24:10
%S 16,81,144,324,400,625,784,1936,2025,2401,2500,2704,3600,3969,4624,
%T 5625,5776,7056,8100,8464,9604,9801,13456,13689,14641,15376,15876,
%U 17424,19600,21609,21904,22500,23409,24336,26896,28561,29241,29584,30625,35344,39204,41616,42849
%N Squares divisible by a single cube > 1.
%C Numbers whose prime factorization has a single exponent that is equal to 4 and all the rest, if they exist, are equal to 2. - _Amiram Eldar_, Jun 25 2022
%H Hugo Pfoertner, <a href="/A320965/b320965.txt">Table of n, a(n) for n = 1..10000</a>
%F From _Amiram Eldar_, Jun 25 2022: (Start)
%F a(n) = A060687(n)^2.
%F Sum_{n>=1} 1/a(n) = (15/Pi^2) * Sum_{k>=2} (-1)^k * P(2*k) = 0.09603403868516162554..., where P(s) is the prime zeta function. (End)
%t sdscQ[n_]:=Count[Rest[Divisors[n]],_?(IntegerQ[Surd[#,3]]&)]==1; Select[ Range[ 250]^2,sdscQ] (* _Harvey P. Dale_, Aug 18 2020 *)
%t q[n_] := (e = Sort[FactorInteger[n][[;;, 2]], Greater])[[1]] == 4 && AllTrue[Rest[e], # == 2 &]; Select[Range[200]^2, q] (* _Amiram Eldar_, Jun 25 2022 *)
%Y Cf. A000290, A000578, A046099, A060687, A062320, A216427, A320966, A321070.
%K nonn
%O 1,1
%A _Hugo Pfoertner_, Oct 25 2018