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.

A255681 Decimal expansion of Sum_{k>=1} zeta(2*k+1)/((2*k+1)*2^(2*k)).

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Apr 13 2015

Keywords

Examples

			0.1159315156584124488107200313757741370333407984203316553149...
		

Crossrefs

Cf. A001620, A002162, A094642 (= log(Pi/2) = Sum_{k>=2} zeta(2*k)/(k*2^(2*k))).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); Log(2) - EulerGamma(R); // G. C. Greubel, Sep 06 2018
  • Mathematica
    RealDigits[Log[2] - EulerGamma, 10, 105] // First
  • PARI
    default(realprecision, 100); log(2) - Euler \\ G. C. Greubel, Sep 06 2018
    

Formula

Equals log(2) - EulerGamma.
Equals Sum_{k>=1} (zeta(2*k+1)-1)/(k+1). - Amiram Eldar, May 24 2021
Equals Sum_{k>=1} psi(k)/2^k, where psi(x) is the digamma function. - Amiram Eldar, Sep 12 2022