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.

A333972 Decimal expansion of Pi^6/540 = zeta(2) * zeta(4).

Original entry on oeis.org

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

Views

Author

Bernard Schott, Sep 29 2020

Keywords

Comments

Compare 1st formula with Sum_{m>0, q>0} 1/(m^2*q^2) = Pi^4/36 = (zeta(2))^2 = A098198.

Examples

			1.78035035847278599450040637713411092382818060755749373322421516...
		

References

  • Jean-Marie Monier, Analyse, Exercices corrigés, 2ème année MP, Dunod, 1997, Exercice 3.22, p. 275.

Crossrefs

Programs

  • Maple
    evalf(Pi^6/540,120);
  • Mathematica
    RealDigits[Pi^6/540, 10, 100][[1]] (* Amiram Eldar, Sep 29 2020 *)
  • PARI
    Pi^6/540 \\ Michel Marcus, Sep 30 2020

Formula

Equals Sum_{m>0, q>0, m | q} 1/(m^2*q^2).
Equals A013661 * A068447.
Equals Sum_{k>=1} sigma_2(k)/k^4. - Amiram Eldar, Sep 30 2020
Equals Sum_{k>=1} A046951(k)/k^2. - Amiram Eldar, Jan 25 2024