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.

Showing 1-4 of 4 results.

A306243 Decimal expansion of Sum_{n>=2} log(n)/n!.

Original entry on oeis.org

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

Views

Author

Rok Cestnik, Jan 31 2019

Keywords

Examples

			0.6037828627914879884...
		

Crossrefs

Programs

  • Mathematica
    NSum[Log[n]/n!, {n, 2, Infinity}, WorkingPrecision -> 110,
      NSumTerms -> 100] // RealDigits[#, 10, 100] &
  • PARI
    suminf(n=2, log(n)/n!) \\ Michel Marcus, Jan 31 2019

Formula

Equal to log(exp(1/2*log(2*exp(1/3*log(3*exp(1/4*log(4*exp(...)))))))).
Equals log(A296301). - Vaclav Kotesovec, Jun 22 2023
Equals Integral_{x=0..2*Pi} log(Gamma(x/(2*Pi))) * exp(cos(x)) * sin(x + sin(x)) dx - (e-1)*(log(2*Pi)+gamma), where gamma is Euler's constant (A001620) (Mező, 2014). - Amiram Eldar, Jan 25 2024
Equals Integral_{x=0..1} (exp(x) - 1)/(x*log(x)) - (exp(1) - 1)/log(x) dx. - Velin Yanev, Nov 29 2024

A296547 Decimal expansion of (2 + (3 + (4 + (5 + ...)^(1/5))^(1/4))^(1/3))^(1/2).

Original entry on oeis.org

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

Views

Author

Ilya Gutkovskiy, Dec 15 2017

Keywords

Examples

			1.9116392162458242838833095376406246646085815394...
		

Crossrefs

A385686 Decimal expansion of exp((Sum_{k>=2} log(k)/k!)/(e-1)).

Original entry on oeis.org

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

Views

Author

Jwalin Bhatt, Jul 06 2025

Keywords

Comments

The geometric mean of the Poisson distribution with parameter value 1 (A385685) approaches this constant.

Examples

			1.4210379597319607153378144890592856953982...
		

Crossrefs

Programs

  • Mathematica
    N[Exp [Sum[Log[i]/Factorial[i], {i, 2, Infinity}] / (E-1) ], 120]
  • PARI
    prodinf(k=2, k^(1/k!))^(1/(exp(1)-1))

Formula

Equals exp((Sum_{k>=2} log(k)/k!)/(e-1)).
Equals (Product_{k>=2} k^(1/k!)) ^ (1/(e-1)).
From Vaclav Kotesovec, Jul 08 2025: (Start)
Equals exp(A306243/(exp(1) - 1)).
Equals A296301^(1/(exp(1) - 1)). (End)

A363767 Decimal expansion of 2^(e-2)*e^Sum_{k=2..oo} log(k)/k!.

Original entry on oeis.org

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

Views

Author

Stefano Spezia, Jun 21 2023

Keywords

Examples

			3.009150722741487993563074737485316800510...
		

Crossrefs

Programs

  • Mathematica
    2^(E-2)E^NSum[Log[n]/n!, {n, 2, Infinity}, WorkingPrecision -> 110, NSumTerms -> 100] // RealDigits[#, 10, 100] &//First

Formula

Equals 2^(e-2)*e^A306243.
Equals 2^(exp(1)-2)*A296301. - Vaclav Kotesovec, Jun 22 2023
Showing 1-4 of 4 results.