

A135002


Decimal expansion of 2/e.


4



7, 3, 5, 7, 5, 8, 8, 8, 2, 3, 4, 2, 8, 8, 4, 6, 4, 3, 1, 9, 1, 0, 4, 7, 5, 4, 0, 3, 2, 2, 9, 2, 1, 7, 3, 4, 8, 9, 1, 6, 2, 2, 2, 6, 2, 0, 6, 3, 5, 3, 5, 6, 6, 9, 0, 1, 5, 6, 7, 3, 6, 0, 3, 3, 9, 4, 9, 2, 2, 9, 9, 1, 4, 8, 9, 7, 9, 9, 6
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OFFSET

0,1


COMMENTS

From Johannes W. Meijer, Jun 27 2016: (Start)
This constant is related to the values of zeta(2*n1) of the Riemann zeta function and the Euler Mascheroni constant gamma. If we define Z(n) = (1/n) * (sum(zeta(2*n2*k1) * Z(k), k=0..n2) + gamma * Z(n1)), with Z(0) = 1, then limit(Z(n), n > infinity) = 2/exp(1).
Similar formulas appear in A163930 and A112302.
The structure of the n! * Z(n) formulas leads to the multinomial coefficients A036039. (End).


LINKS

Table of n, a(n) for n=0..78.


FORMULA

Integral of log x from x = 1/e to e.  Charles R Greathouse IV, Apr 16 2015
Equals lim_{k>0} 2*(1  k)^(1/k).  Ilya Gutkovskiy, Jun 27 2016


EXAMPLE

0.735758882342... = 2*A068985.


MAPLE

evalf(2/exp(1)) ; # R. J. Mathar, Jul 14 2013


MATHEMATICA

RealDigits[2/E, 10, 120][[1]] (* Harvey P. Dale, Dec 25 2013 *)


PROG

(PARI) 2*exp(1) \\ Charles R Greathouse IV, Apr 16 2015


CROSSREFS

Sequence in context: A213085 A119714 A154889 * A175452 A084714 A256779
Adjacent sequences: A134999 A135000 A135001 * A135003 A135004 A135005


KEYWORD

cons,nonn


AUTHOR

Omar E. Pol, Nov 15 2007


STATUS

approved



