OFFSET
1,4
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
Steven R. Finch, Tauberian Constants, August 30, 2004 [Cached copy, with permission of the author]
Eric Weisstein's MathWorld, Exponential Integral
FORMULA
Also equals gamma + 2*G/e, where G is the Euler-Gompertz constant 0.596347...
EXAMPLE
1.01598353369257340796083964100264572910425392275374...
MAPLE
evalf(gamma - 2*Ei(-1), 120); # Vaclav Kotesovec, Oct 27 2014
MATHEMATICA
RealDigits[ EulerGamma - 2*ExpIntegralEi[-1], 10, 103] // First
PROG
(PARI) default(realprecision, 100); Euler + 2*eint1(1) \\ G. C. Greubel, Sep 04 2018
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Oct 27 2014
STATUS
approved