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Decimal expansion of Sum_{n>=1} 1/n^(n^n).
2

%I #10 Nov 11 2017 20:45:18

%S 1,0,6,2,5,0,0,0,0,0,0,0,0,1,3,1,1,3,7,2,6,5,2,3,9,7,0,9,2,5,0,7,2,3,

%T 4,6,8,5,5,1,9,5,4,3,1,3,5,3,0,2,4,9,9,3,8,9,7,5,8,8,2,5,2,3,8,0,8,1,

%U 2,4,4,5,5,8,1,2,3,3,1,0,9,3,4,1,4,0,6,0,5,6,4,4,9,0,2,3,0,6,0,2,2,1,7,3,1

%N Decimal expansion of Sum_{n>=1} 1/n^(n^n).

%C A more general function is L(z) = sum(n=1,Infinity,1/n^^z).

%C What is the value of L(4)?

%C L(4) = 1.0000152587890625000... where the next 3 trillion decimal places are 0. - _Charles R Greathouse IV_, Sep 20 2012

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Tetration">Tetration</a>

%e 1.062500000000131137265239709250723468551954313530249 . . .

%o (PARI) suminf(n=1,1/n^(n^n))

%Y Cf. A073009, A002488.

%K cons,nonn

%O 1,3

%A _Balarka Sen_, Aug 16 2012