OFFSET
0,1
COMMENTS
See crossrefs sequences for other comments, references, links, and formulas.
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..10000
J. C. Lagarias, Euler's constant: Euler's work and modern developments, arXiv:1303.1856 [math.NT], 2013-2014; Bull. Amer. Math. Soc., 50 (2013), 527-628; see p. 553.
FORMULA
Equals Sum_{n>=1} (-1)^(n-1) / A001563(n) = Sum_{n>=1} (-1)^(n-1) / (n*n!).
Equals -Integral_{x=0..1} log(x)/exp(x) dx. - Amiram Eldar, Aug 01 2020
Equals (1/e) * Sum_{k>=1} H(k)/k!, where H(k) = A001008(k)/A002805(k) is the k-th harmonic number. - Amiram Eldar, Jun 25 2021
EXAMPLE
0.7965995992970531342836758655425240800732066293468...
MATHEMATICA
RealDigits[EulerGamma - ExpIntegralEi[-1], 10, 100][[1]]
PROG
(PARI) Euler + eint1(1, 1)[1] \\ Michel Marcus, Aug 01 2020
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Jonathan Sondow, Mar 12 2014
STATUS
approved