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%I #11 Mar 03 2016 13:22:35
%S 3,5,1,5,2,5,9,6,9,0,7,1,3,0,8,9,9,7,4,2,3,1,4,7,3,6,1,5,7,9,0,8,6,9,
%T 6,5,9,2,6,8,0,0,8,0,9,1,5,1,2,1,5,8,7,5,9,1,5,4,0,4,2,8,0,4,2,9,7,7,
%U 7,5,7,8,9,6,9,4,5,6,7,8,9,1,7,4,9,4,5,0,2,9,6,6,5,1,8,9,0,5,7,4,0,4,3,7,8
%N Decimal expansion of the solution of agm(x,2) = 1.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Arithmetic-GeometricMean.html">Arithmetic-Geometric Mean</a>
%H Wolfram Research, <a href="http://functions.wolfram.com/EllipticFunctions/ArithmeticGeometricMean/">Arithmetic-Geometric Mean</a>
%e agm(0.351525969,2) = 1.
%t digits = 105; x /. FindRoot[ ArithmeticGeometricMean[x, 2] == 1, {x, 1}, WorkingPrecision -> digits+5] // RealDigits[#, 10, digits]& // First (* _Jean-François Alcover_, Mar 05 2013 *)
%o (PARI) solve(x=0,1/2,agm(x,2)-1)
%K nonn,cons
%O 0,1
%A _Robert G. Wilson v_, Oct 19 2002
%E More terms from _Benoit Cloitre_, Oct 20 2002