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.

A358516 Decimal expansion of Sum_{k >= 1} (-1)^(k+1)*1/((k+2)*(k+3)).

Original entry on oeis.org

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

Views

Author

Claude H. R. Dequatre, Nov 20 2022

Keywords

Examples

			0.0529610277865572855011309095830198028176669353...
		

Crossrefs

Programs

  • Mathematica
    Join[{0}, RealDigits[2*Log[2] - 4/3, 10, 120][[1]]] (* Amiram Eldar, Nov 21 2022 *)
  • PARI
    2*log(2) - 4/3

Formula

Equals Sum_{k >= 1} (-1)^(k+1)*/((k+2)*(k+3)) = A016627 -4/3.
Equals 2*log(2) - 4/3 = Sum_{k >= 2} 1/(4*k^3 - k) = Sum_{k >= 1} (zeta(2*k + 1) - 1)/(4^k). [from the Shamos reference]
Equals Sum_{k >= 1} 1/((2^k)*(4*k + 12)). [from the Shamos reference]
Equals Sum_{k>=3} (-1)^(k+1)/A002378(k). - Amiram Eldar, Nov 21 2022

Extensions

Missing terms 6, 0 inserted after a(74) by Georg Fischer, Feb 07 2025