OFFSET
0,1
FORMULA
Equals Sum_{k>=1} (-1)^(k+1) * H(k) / k!, where H(k) is the k-th harmonic number.
Equals -Integral_{x=0..1} exp(-x)*log(1-x) dx. - Amiram Eldar, Oct 23 2021
EXAMPLE
0.48482910699568764631040141422173057472446995282397321...
MATHEMATICA
RealDigits[Exp[-1] (ExpIntegralEi[1] - EulerGamma), 10, 110] [[1]]
PROG
(PARI) (-real(eint1(-1))-Euler)/exp(1) \\ Michel Marcus, Oct 24 2021
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Ilya Gutkovskiy, Oct 23 2021
STATUS
approved