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A125313
Decimal expansion of 2*exp(-gamma).
1
1, 1, 2, 2, 9, 1, 8, 9, 6, 7, 1, 3, 3, 7, 7, 0, 3, 3, 9, 6, 4, 8, 2, 8, 6, 4, 2, 9, 5, 8, 1, 7, 6, 1, 5, 7, 3, 5, 3, 1, 4, 2, 0, 7, 7, 3, 8, 5, 0, 3, 0, 6, 3, 3, 6, 3, 0, 8, 3, 1, 8, 1, 5, 2, 0, 9, 0, 1, 7, 5, 9, 3, 4, 1, 4, 8, 5, 7, 1, 2, 7, 4, 2, 6, 5, 7, 4, 2, 3, 1, 7, 8, 6, 8, 4, 2, 8, 7, 1, 7, 5, 3, 4, 6, 3
OFFSET
1,3
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.3, Landau-Ramanujan constant, p. 100.
LINKS
A. Granville, Harald Cramér and the distribution of prime numbers, Scandinavian Actuarial Journal 1: 12-28, (1995) DOI:10.1080/03461238.1995.10413946.
Bernard Montaron, Exponential prime sequences, arXiv:2011.14653 [math.NT], 2020.
Simon Plouffe, Plouffe's Inverter.
S. K. Wilson and B. R. Duffy, An asymptotic analysis of small holes in thin fluid layers, Journal of Engineering Mathematics, July 1996, Volume 30, Issue 4, pp 445-457.
FORMULA
Equals 2*A080130, 2*A001113^(-A001620) and 2/A073004 = 2/A068985^A001620.
Equals A088540 * A088541. - Jean-François Alcover, Jun 04 2014
Equals exp(A002162 - A001620). - John W. Nicholson, Apr 03 2015
EXAMPLE
1.12291896713377033964828642958176157353142077385030633630831815209...
MATHEMATICA
RealDigits[2*Exp[-EulerGamma], 10, 111][[1]]
PROG
(PARI) default(realprecision, 100); 2*exp(-Euler) \\ G. C. Greubel, Sep 05 2018
(Magma) R:= RealField(100); 2*Exp(-EulerGamma(R)); // G. C. Greubel, Sep 05 2018
CROSSREFS
Sequence in context: A351400 A176020 A048650 * A199058 A274569 A082838
KEYWORD
cons,nonn
AUTHOR
Robert G. Wilson v, Dec 08 2006
STATUS
approved