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%I #14 Jul 23 2021 02:07:03
%S 1,4182,4879,122664360,315870765,4621320120,5006430130,20245909880,
%T 220899101736,239307360214,812593845485
%N Numbers k such that sum of squares of divisors of k is a cube.
%C It is known that A006532 is an infinite sequence. Is this sequence infinite?
%C a(12) > 10^12. - _Giovanni Resta_, Aug 14 2017
%H Giovanni Resta, <a href="/A290846/a290846.txt">A list of 3110 terms > 10^12</a>
%e 4879 is a term because 1^2 + 7^2 + 17^2 + 41^2 + 119^2 + 287^2 + 697^2 + 4879^2 = 290^3.
%o (PARI) isok(n) = ispower(sigma(n, 2), 3);
%Y Cf. A001157, A006532, A046655.
%K nonn,more
%O 1,2
%A _Altug Alkan_, Aug 12 2017
%E a(6)-a(11) from _Giovanni Resta_, Aug 14 2017