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.

A193424 Decimal expansion of Sum_{n>=1} log(n+1)/n!.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Aug 23 2011, based on a posting by Richard C. Schroeppel to the Math Fun Mailing List

Keywords

Comments

Equal to log(2*exp(1/2*log(3*exp(1/3*log(4*exp(...)))))). - Rok Cestnik, Jan 31 2019

Examples

			1.55867043642538904...
		

Crossrefs

Cf. A306243.

Programs

  • Mathematica
    NSum[ Log[n + 1]/n!, {n, 1, Infinity}, WorkingPrecision -> 110, NSumTerms -> 100] // RealDigits[#, 10, 105]& // First (* Jean-François Alcover, Feb 20 2013 *)
  • PARI
    suminf(n=1, log(n+1)/n!) \\ Michel Marcus, Jan 31 2019

Extensions

More terms from Alois P. Heinz, Aug 28 2011

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)

A336730 Decimal expansion of Sum_{n>=1} log(n)^n / n!.

Original entry on oeis.org

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

Views

Author

Bernard Schott, Aug 02 2020

Keywords

Comments

With u(n) = log(n)^n / n!, this series is convergent as u(n+1)/u(n) -> 0 when n -> oo.

Examples

			0.785672099547734935860778589192856069327...
		

References

  • Jean-Marie Monier, Analyse, Exercices corrigés, 2ème année, MP, Dunod, 1997, Exercice 3.2.1.r page 279.

Crossrefs

Programs

  • Maple
    evalf(sum(log(n)^n/n!,n=2..infinity),120);
  • PARI
    suminf(n=1, log(n)^n/n!) \\ Michel Marcus, Aug 02 2020

Formula

Equals Sum_{n>=1} log(n)^n / n!.

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.