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.

User: Alejandro Malla

Alejandro Malla's wiki page.

Alejandro Malla has authored 2 sequences.

A367309 Decimal expansion of area under the curve (1-2^(1-x))*zeta(x) from 0 to 1.

Original entry on oeis.org

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

Author

Alejandro Malla, Nov 13 2023

Keywords

Comments

The series Sum_{n >= 1} (-1)^(n+1)/n^x converges nonuniformly to g(x) = (1 - 2^(1-x))*zeta(x) on the open interval (0, 1). This series can be described as an alternating version of the 'p-series' when 0 < p < 1. Let f(x) = Sum_{n >= 1} (-1)^(n+1)/n^x. Then f(0+) = g(0) = 1/2 and f(1) = log(2), whereas g(1) is undefined, but has the limit value log(2). Also, f(1/2) = g(1/2) = A113024 = 0.604898643421... .

Examples

			0.60211234931037155497112632...
		

Crossrefs

Programs

  • Mathematica
    y = NIntegrate[(1 - 2^(1-x)) Zeta[x], {x, 0, 1}, WorkingPrecision -> 200]
    RealDigits[y][[1]]
  • PARI
    intnum(x=0, 1, (1-2^(1-x))*zeta(x)) \\ Michel Marcus, Nov 14 2023

A367310 Continued fraction of the constant in A367309 (the area under the curve (1 - 2^(1-x)) zeta(x) from 0 to 1).

Original entry on oeis.org

0, 1, 1, 1, 1, 18, 2, 1, 37, 3, 1, 2, 20, 1, 3, 3, 1, 1, 1, 1, 2, 1, 26, 1, 1, 1, 2, 4, 3, 1, 76, 1, 3, 1, 1, 2, 1, 1, 3, 5, 3, 1, 10, 2, 5, 1, 3, 8, 1, 3, 2, 2, 5, 2, 1, 1, 1, 6, 2, 36, 5, 1, 2, 1, 1, 1, 9, 4, 3, 1, 1, 4, 1, 1, 2, 1, 1, 3, 1, 2, 1, 1, 29, 1
Offset: 0

Author

Alejandro Malla, Nov 13 2023

Keywords

Crossrefs

Programs

  • Mathematica
    ContinuedFraction[NIntegrate[(1 - 2^(1-x)) Zeta[x], {x,0,1}, WorkingPrecision ->300]]
  • PARI
    localprec(100); contfrac(intnum(x=0, 1, (1-2^(1-x))*zeta(x))) \\ Michel Marcus, Nov 14 2023