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A386714
Decimal expansion of Integral_{x=0..1} {1/x}^3 * {1/(1-x)}^3 dx, where {} denotes fractional part.
1
0, 1, 4, 6, 1, 1, 7, 0, 2, 6, 1, 6, 5, 3, 2, 6, 9, 5, 6, 8, 4, 2, 7, 2, 0, 3, 5, 4, 7, 3, 8, 7, 3, 5, 6, 5, 0, 7, 6, 0, 6, 8, 1, 1, 5, 0, 2, 6, 8, 3, 5, 6, 1, 6, 8, 7, 0, 7, 2, 8, 0, 1, 8, 3, 5, 6, 3, 5, 6, 5, 4, 6, 7, 9, 9, 4, 4, 6, 5, 8, 5, 9, 8, 3, 1, 9, 6, 3, 1, 7, 5, 9, 4, 3, 4, 6, 3, 7, 1, 1, 5, 7, 3, 9, 8
OFFSET
0,3
REFERENCES
Ovidiu Furdui, Limits, Series, and Fractional Part Integrals: Problems in Mathematical Analysis, New York: Springer, 2013. See section 2.11, page 101.
LINKS
Ovidiu Furdui, A class of fractional part integrals and zeta function values, Integral Transforms and Special Functions, Vol. 24, No. 6 (2013), pp. 485-490.
FORMULA
Equals -zeta(2) + 3*gamma + 36*log(A) - 6*log(2*Pi) + 2, where gamma is Euler's constant and A is the Glaisher-Kinkelin constant.
In general, for m >= 2, Integral_{x=0..1} {1/x}^m * {1/(1-x)}^m dx = 2 * (Sum_{j=2..m-1} (-1)^(m+j-1) * (zeta(j)-1)) + (-1)^m - (2*m) * Sum_{k>=0} (zeta(2*k+m) - zeta(2*k+m+1))/(k+m) (note that the first sum vanishes when m = 2).
EXAMPLE
0.01461170261653269568427203547387356507606811502683...
MATHEMATICA
RealDigits[-Zeta[2] + 3*EulerGamma + 36*Log[Glaisher] - 6*Log[2*Pi] + 2, 10, 120, -1][[1]]
PROG
(PARI) -zeta(2) + 3*Euler + 36*(1/12-zeta'(-1)) - 6*log(2*Pi) + 2
CROSSREFS
Cf. A001620 (gamma), A013661, A061444, A074962 (A), A225746.
Cf. A147533 (m=1), A386713 (m=2), this constant (m=3).
Sequence in context: A107951 A019646 A238582 * A396444 A395934 A384213
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Jul 31 2025
STATUS
approved