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A308577
Decimal expansion of Integral_{x=0..infinity} exp(-x)/(1 + erf(sqrt(x))).
0
5, 9, 8, 5, 0, 1, 7, 9, 2, 4, 4, 9, 0, 6, 1, 8, 3, 0, 0, 1, 7, 9, 9, 8, 8, 3, 7, 6, 6, 1, 6, 1, 7, 5, 7, 4, 9, 1, 4, 6, 8, 8, 9, 6, 5, 5, 2, 2, 9, 0, 5, 4, 0, 2, 8, 1, 1, 2, 2, 8, 8, 7, 5, 1, 7, 7, 5, 1, 9, 2, 1, 3, 0, 6, 1, 0, 9, 5, 7, 9, 0, 9, 6, 1, 2, 1, 8, 6, 4, 4, 6, 9, 7, 5, 0, 5, 4, 0, 8, 6, 8, 0, 2, 3, 9, 3
OFFSET
0,1
EXAMPLE
Equals 0.5985017924490618300179988376616175749146889655229...
MAPLE
evalf(Int(exp(-x)/(1 + erf(sqrt(x))), x=0..infinity, method=_Gquad), 110);
MATHEMATICA
RealDigits[NIntegrate[1/(E^z (1 + Erf[Sqrt[z]])), {z, 0, Infinity}, PrecisionGoal -> 20]][[1]]
(* Second program: *)
digits = 105; dz = 50;
f[z0_] := f[z0] = NIntegrate[1/(E^z (1 + Erf[Sqrt[z]])), {z, 0, z0}, WorkingPrecision -> digits+5] + 1/(2 E^z0) // RealDigits[#, 10, digits][[1]]&; f[z0 = dz]; f[z0 = z0 + dz];
While[Print["z0 = ", z0]; f[z0] != f[z0 - dz], z0 = z0 + dz];
f[z0] (* Jean-François Alcover, Jun 18 2019 *)
CROSSREFS
Sequence in context: A249385 A347216 A247747 * A217249 A091812 A112678
KEYWORD
nonn,cons
AUTHOR
Peter Luschny, Jun 08 2019
EXTENSIONS
More digits from Jean-François Alcover, Jun 18 2019
STATUS
approved