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%I #6 May 25 2018 08:28:23
%S 1,1,9,7,3,7,2,7,6,4,5,3,8,1,8,8,8,6,1,7,1,3,4,7,7,9,5,4,2,0,5,3,7,8,
%T 1,9,7,8,1,9,0,2,8,2,1,3,9,9,0,3,7,2,1,9,0,1,3,0,7,7,2,4,5,1,4,0,3,0,
%U 3,6,4,7,6,9,4,0,3,4,2,6,7,9,0,9,2,1,2,7,5,4,9,1,4,4,3,1,4,1,0,4,3,1,1,2,2
%N Decimal expansion of alpha(2) = Sum_{i>0} prime(i)*2^(-i^2).
%C prime(n) = floor(2^(n^2)*alpha(2))-2^(2*n-1)*floor(2^((n-1)^2)*alpha(2)). For n = 6 we have prime(6) = floor(2^36*alpha(2))-2^11*floor(2^25*alpha(2)) = 82282829837-2048*40177163 = 13.
%D G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, Clarendon Press, Oxford, 1979, page 345.
%e alpha(2) = 1.19737276453818886171347795420537819781902821399037219013\
%e 077245140303647694034267909212754914431410431122998171762351103482006\
%e 076264716653454638...
%o (PARI) suminf(i=1, prime(i)/2^(i^2)) \\ _Michel Marcus_, May 25 2018
%K nonn,cons
%O 1,3
%A _Vladeta Jovovic_, Apr 03 2001