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.

A382907 Decimal expansion of 1/2 - Pi*(sqrt(2)+1)/16.

Original entry on oeis.org

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

Views

Author

Sean A. Irvine, Apr 08 2025

Keywords

Examples

			0.02597027551574003215759...
		

Crossrefs

Programs

  • Mathematica
    Join[{0},RealDigits[1/2-(Pi(Sqrt[2]+1))/16,10,120][[1]]] (* Harvey P. Dale, Apr 30 2025 *)

Formula

Equals Sum_{k>=1} 1/((8*k-1)*(8*k+1)).
From Amiram Eldar, Aug 08 2025: (Start)
Equals Sum_{k>=1} 1/A158684(k).
Equals (1 - cot(Pi/8)*Pi/8)/2. (End)