cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A369633 Decimal expansion of integral of frac(1/x)^3 dx for x=0 to 1.

Original entry on oeis.org

1, 8, 7, 0, 7, 3, 0, 7, 2, 5, 0, 9, 7, 7, 9, 7, 8, 9, 4, 5, 0, 9, 5, 9, 1, 5, 7, 6, 7, 7, 7, 6, 6, 6, 3, 1, 9, 5, 7, 8, 1, 4, 8, 0, 2, 9, 6, 2, 2, 1, 5, 9, 3, 7, 6, 4, 6, 5, 5, 3, 5, 4, 8, 4, 1, 9, 2, 7, 1, 1, 6, 3, 0, 0, 4, 6, 5, 3, 4, 8, 5, 5, 9, 0, 1, 3, 2, 2, 3, 0, 6, 2, 1, 0, 6, 3, 3, 1, 0, 1
Offset: 0

Views

Author

Benoit Cloitre, Jan 28 2024

Keywords

Examples

			0.18707307250977978945095915767776663195781480296221...
		

References

  • Ovidiu Furdui, Limits, Series, and Fractional Part Integrals, Problems in Mathematical Analysis, Springer, 2013. See p. 100.

Crossrefs

Programs

  • Mathematica
    RealDigits[3*Log[2*Pi]/2 - 6*Log[Glaisher] - EulerGamma - 1/2, 10, 120][[1]] (* Amiram Eldar, Jan 28 2024 *)
  • PARI
    3*log(2*Pi)/2 + 6*zeta'(-1) - Euler - 1 \\ Amiram Eldar, Jan 28 2024

Formula

Integral_{x=0..1} frac(1/x)^3 dx = (3/2)*log(2*Pi) - 6*log(A) - gamma - 1/2 = 0.1870730725..., where A is the Glaisher-Kinkelin constant.
Equals 3*log(2) - 3/2 + 3 * Sum_{k>=1} ((-1)^k/(k+3))*(zeta(k+1)-1).
From Vaclav Kotesovec, Jan 29 2024: (Start)
Equals 6 * Sum_{k>=1} (zeta(k+1) - 1) / ((k+1)*(k+2)*(k+3)).
Equals -1/2 + 6 * Sum_{k>=2} zeta(k) / (k*(k+1)*(k+2)). (End)