OFFSET
1,2
FORMULA
Equals Integral_{0..oo} (x^(1/x-x)) dx (definition).
Equals Integral_{0..1} (x^(1/x-x) * (1 + 1/x^2) ) dx.
Equals Integral_{0..oo} ( (x + sqrt(x^2 + 4))/2 )^(-x) dx.
EXAMPLE
1.3207304008696366654886148277807262075232447951825960706678785858663...
MAPLE
evalf(Int(x^(1/x-x), x = 0..infinity), 120);
MATHEMATICA
RealDigits[NIntegrate[x^(1/x - x), {x, 0, Infinity}, WorkingPrecision -> 120]][[1]] (* Vaclav Kotesovec, Jan 15 2019 *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Sam Coutteau, Sep 28 2018
EXTENSIONS
More terms from Vaclav Kotesovec, Jan 15 2019
STATUS
approved