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%I #3 Mar 30 2012 17:39:33
%S 4,64,65536,1073741824,309485009821345068724781056,
%T 85070591730234615865843651857942052864
%N Bisection of even superperfect numbers A061652.
%C Also, bisection of superperfect numbers A019279, if there are no odd superperfect numbers.
%C Next terms have 183, 663 and more digits and are therefore not listed. - _R. J. Mathar_, May 22 2008
%Y Cf. A019279, A061652, A099057, A099058, A134721, A134722, A138834.
%K nonn
%O 1,1
%A _Omar E. Pol_, Apr 06 2008