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%I #12 Nov 14 2012 00:54:08
%S 11,14,15,91,92,132,140,991,1891,3525,3792,4025,4650,5775,6384,45847,
%T 78337,99904,105664,180544,133152769,134176771,227512999,233016679,
%U 451443979,865079296,1478127616,1509765120,1585188864,1660973056,1793101824,3063803904
%N Numbers n such that sigma(n)/tau(n) is a perfect number.
%t perfectQ[n_] := DivisorSigma[1, n] == 2*n; Select[Range[10000], perfectQ[DivisorSigma[1, #] / DivisorSigma[0, #]] &] (* _T. D. Noe_, Nov 13 2012 *)
%Y Subsequence of A003601.
%Y Cf. A000396 (perfect numbers).
%K nonn
%O 1,1
%A _Zdenek Cervenka_, Nov 13 2012
%E a(21)-a(32) from _Donovan Johnson_, Nov 13 2012
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