OFFSET
1,1
FORMULA
Equals Sum_{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
2.16538221532693635942098634849243056838142076774144369...
MATHEMATICA
RealDigits[Exp[1] (EulerGamma - ExpIntegralEi[-1]), 10, 110] [[1]]
PROG
(PARI) exp(1)*(Euler + eint1(1)) \\ Michel Marcus, Oct 24 2021
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Ilya Gutkovskiy, Oct 23 2021
STATUS
approved