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A273017 Decimal expansion of the first moment of the reciprocal gamma distribution. 1
1, 9, 3, 4, 5, 6, 7, 0, 4, 2, 1, 4, 7, 8, 8, 4, 7, 2, 1, 1, 8, 3, 7, 1, 4, 7, 0, 4, 3, 6, 9, 1, 7, 8, 9, 2, 4, 3, 8, 2, 1, 7, 5, 5, 9, 2, 2, 6, 6, 5, 8, 8, 4, 8, 3, 8, 5, 5, 4, 4, 7, 5, 4, 2, 2, 5, 9, 5, 4, 4, 0, 8, 7, 4, 7, 1, 0, 1, 8, 2, 4, 7, 2, 2, 5, 4, 4, 5, 0, 0, 3, 8, 3, 4, 8, 2, 1, 0, 1, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 4.6 Fransén-Robinson constant, p. 262.

LINKS

Table of n, a(n) for n=1..100.

Steven R. Finch Errata and Addenda to Mathematical Constants p. 35.

Steven R. Finch, Errata and Addenda to Mathematical Constants, January 22, 2016. [Cached copy, with permission of the author]

Eric Weisstein's MathWorld Fransén-Robinson Constant

Wikipedia, Reciprocal gamma function

FORMULA

(1/I)*Integral_{x>=0} x/gamma(x) dx where I = Integral_{x>=0} 1/gamma(x) dx is the Fransén-Robinson constant.

EXAMPLE

1.93456704214788472118371470436917892438217559226658848385544754...

MATHEMATICA

digits = 100;

I0 = NIntegrate[1/Gamma[x], {x, 0, Infinity}, WorkingPrecision -> digits + 5];

M1 = (1/I0) NIntegrate[x/Gamma[x], {x, 0, Infinity}, WorkingPrecision -> digits + 5];

RealDigits[M1, 10, digits][[1]]

PROG

(PARI) default(realprecision, 120); intnum(x=0, [[1], 1], x/gamma(x))/intnum(x=0, [[1], 1], 1/gamma(x)) \\ Vaclav Kotesovec, May 14 2016

CROSSREFS

Cf. A058655.

Sequence in context: A011011 A236100 A070634 * A222233 A021111 A242302

Adjacent sequences:  A273014 A273015 A273016 * A273018 A273019 A273020

KEYWORD

nonn,cons

AUTHOR

Jean-François Alcover, May 13 2016

STATUS

approved

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)