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%I #6 Nov 21 2013 12:48:11
%S 1,27,823543,437893890380859375,
%T 17069174130723235958610643029059314756044734431,
%U 228273036346967044979900512337165522400819024722490933829954793073267717315004135590642802687246850771579138342847
%N (2^n - 1)^(2^n - 1).
%F A000225(n)^A000225(n)
%t f[n_]:=Module[{x=2^n-1},x^x]
%t f/@Range[6] (* _Harvey P. Dale_, Feb 26 2011 *)
%Y Cf. A000225.
%K easy,nonn
%O 1,2
%A _Zak Seidov_, Aug 25 2003