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.

A318741 Decimal expansion of Pi^3/48 + Pi*log(2)^2/4.

Original entry on oeis.org

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

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Author

Hugo Pfoertner, Sep 17 2018

Keywords

Comments

The first part of Ramanujan's question 308 in the Journal of the Indian Mathematical Society (III, 168) asked "Show that Integral_{t=0..Pi/2} t * cotan(t) * log(sin(t)) dt = -Pi^3/48 - Pi*log(2)^2/4".

Examples

			1.0233110122363703230848205040884867383187209767473281303051342763...
		

Programs

  • Mathematica
    RealDigits[Pi^3/48 + Pi*Log[2]^2/4, 10, 100][[1]] (* Amiram Eldar, Oct 04 2021 *)
  • PARI
    Pi^3/48+Pi*log(2)^2/4
    
  • PARI
    -intnum(x=0,Pi/2,x*cotan(x)*log(sin(x)))

Formula

Equals Sum_{k>=0} binomial(2*k,k)/(4^k*(2*k+1)^3) (Ribeiro, 2018). - Amiram Eldar, Oct 04 2021
Equals 4F3(1/2,1/2,1/2,1/2 ; 3/2,3/2,3/2 ; 1) [Adamchik]. - R. J. Mathar, Aug 19 2024
Equals A196877/2. - R. J. Mathar, Aug 23 2024