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.

A282821 Decimal expansion of Sum_{k >= 0} (4/(4*k+1) - 3/(3*k+1) + 2/(2*k+1) - 1/(k+1)).

Original entry on oeis.org

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

Views

Author

Bruno Berselli, Mar 03 2017

Keywords

Comments

It is known that Sum_{k >= 0} Sum_{i = 1..h} (-1)^i*i/(i*k + 1) diverges for h = 3. This is the case h = 4, A016627 corresponds to the case h = 2.

Examples

			2.48171411447534970392757531472576785936281641070833471570388837547057328...
		

Crossrefs

Cf. A016627.

Programs

  • Mathematica
    RealDigits[(3 - Sqrt[3]) Pi/6 + Log[32] - Log[27]/2, 10, 100][[1]]

Formula

Equals (3 - sqrt(3))*Pi/6 + log(32) - log(27)/2.