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%I #4 Sep 26 2012 13:47:33
%S 1,3,28,72057594037927937
%N a(1) = 1, for n >= 2: a(n) = n^a(n-1) + 1.
%C The next term is too large to include.
%e For n = 3: a(3) = 3^3 + 1 = 28.
%t Transpose[NestList[{#[[1]]+1,(#[[1]]+1)^#[[2]]+1}&,{1,1},3]][[2]] (* _Harvey P. Dale_, Sep 26 2012 *)
%K nonn
%O 1,2
%A _Jaroslav Krizek_, Nov 03 2010