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Cubes of perfect numbers.
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%I #7 Oct 03 2017 20:52:21

%S 216,21952,122023936,536971313152,37765098493683020333056,

%T 633810793114959508165535727616,2596133574015276570584768736919552,

%U 12259964309800138562370625617974597033693433427658801152

%N Cubes of perfect numbers.

%F a(n) = A000396(n)^3

%e a(2)=21952 because the second perfect number is 28 and 28^3=21952.

%t Select[Range[9*10^5], DivisorSigma[1, #] == 2*# &]^3 (* _G. C. Greubel_, Oct 03 2017 *)

%Y Cf. A000578, A030078. Perfect numbers: A000396.

%K nonn

%O 1,1

%A _Omar E. Pol_, Oct 30 2007

%E More terms from _Olaf Voß_, Feb 13 2008