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 1-7 of 7 results.

A100085 Decimal expansion of Sum_{n>0} 1/(n!^n!).

Original entry on oeis.org

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

Views

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 08 2004

Keywords

Comments

This number was called the Pomerance Number, after Carl Pomerance, in the paper by Bailey and Crandall referenced here. The paper by Martin contains a suggestion in its the Acknowledgements section by Carl Pomerance that the number might be "absolutely abnormal".

Examples

			1.250021433470507544581618655692730516577534706218865768307...
		

References

  • G. Harman, One hundred years of normal numbers, in M. A. Bennett et al., eds., Number Theory for the Millennium, II (Urbana, IL, 2000), 149-166, A K Peters, Natick, MA, 2002.

Crossrefs

Programs

  • Mathematica
    RealDigits[ Sum[1/(n!)^(n!), {n, 4}], 10, 111][[1]] (* Robert G. Wilson v, Feb 26 2008 *)
  • PARI
    suminf(n=1, 1/(n!^n!)) \\ Michel Marcus, Dec 22 2016

Extensions

Edited by N. J. A. Sloane, May 16 2008 at the suggestion of R. J. Mathar

A308915 Decimal expansion of Sum_{n>=1} 1/(log(n)^log(n)).

Original entry on oeis.org

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

Views

Author

Bernard Schott, Jun 30 2019

Keywords

Comments

This series is convergent because n^2 * 1/log(n)^log(n) = exp(log(n) * (2 - log(log(n)))) which -> 0 as n -> oo.

Examples

			6.71697061299089608814457...
		

References

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

Crossrefs

Cf. A073009 (1/n^n), A099870 (1/n^log(n)), A099871 (1/log(n)^n).

Programs

  • Maple
    evalf(sum(1/(log(n)^log(n)), n=1..infinity), 110);
  • Mathematica
    RealDigits[N[1 + Sum[1/Log[n]^Log[n], {n, 2, Infinity}], 100]][[1]] (* Jinyuan Wang, Jul 25 2019 *)
  • PARI
    1 + sumpos(n=2, 1/(log(n)^log(n))) \\ Michel Marcus, Jun 30 2019

Formula

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

Extensions

More terms from Jon E. Schoenfield, Jun 30 2019
a(16)-a(24) from Jinyuan Wang, Jul 10 2019
More terms from Charles R Greathouse IV, Oct 21 2021

A100084 Decimal expansion of Sum_{n>0} 1/(n^(n!)).

Original entry on oeis.org

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

Views

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 08 2004

Keywords

Examples

			1.251371742112486405937272764835634431067154077181927...
		

Crossrefs

Programs

  • PARI
    sum(n=1,9,1/(n^(n!)),0.)

A336284 Decimal expansion of Sum_{n>=2} n^(log(n))/log(n)^n.

Original entry on oeis.org

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

Views

Author

Bernard Schott, Jul 17 2020

Keywords

Comments

This series is convergent because there exists n_1 such that for n >= n_1, n^(log(n))/log(n)^n <= (1/sqrt(e))^n.

Examples

			10.5417051152289715912697153360630929474717489965883...
		

Crossrefs

Cf. A073009 (1/n^n), A099870 (1/n^log(n)), A099871 (1/log(n)^n), A308915 (1/(log(n)^log(n))).
Cf. A092605 (1/sqrt(e)).

Programs

  • Maple
    evalf(sum(n^(log(n))/log(n)^n, n=2..infinity),100);
  • PARI
    suminf(n=2, n^(log(n))/log(n)^n) \\ Michel Marcus, Jul 17 2020

Formula

Equals Sum_{n>=2} n^(log(n))/log(n)^n.

A336741 Decimal expansion of Sum_{n>=2} 1/log(n)^sqrt(n).

Original entry on oeis.org

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

Views

Author

Bernard Schott, Aug 02 2020

Keywords

Comments

The series u(n) = 1/log(n)^sqrt(n) is convergent because n^2 * u(n) -> 0 when n -> oo.

Examples

			4.372450021106629664550827989755553790410067553197...
		

References

  • J.-M. Monier, Analyse, Tome 3, 2ème année, MP.PSI.PC.PT, Dunod, 1997, Exercice 3.2.1.d p. 247.

Crossrefs

Programs

  • Maple
    evalf(sum(1/(log(n)^sqrt(n), n=2..infinity), 120);
  • PARI
    sumpos(n=2, 1/log(n)^sqrt(n)) \\ Michel Marcus, Aug 03 2020

Formula

Equals Sum_{n>=2} 1/log(n)^sqrt(n).

Extensions

More terms from Jinyuan Wang, Aug 03 2020

A346670 Decimal expansion of Sum_{n>=1} 1/(n^(log(n)^2)) = Sum_{n>=1} exp(-log(n)^3).

Original entry on oeis.org

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

Views

Author

Jianing Song, Jul 28 2021

Keywords

Comments

An infinite sum that converges faster than A099870.
Note that as p > 0 gets larger and larger, the series Sum_{n>=1} 1/(n^(log(n)^p)) converges faster and faster, but will always converge more slowly than Sum_{n>=0} 1/a^n for every a > 1.

Examples

			2.07138435359817861835919830739134720946...
		

Crossrefs

Programs

  • PARI
    sumpos(n=1, 1/(n^(log(n)^2)))

A336987 Decimal expansion of Sum_{n>=2} sqrt(n)^log(n)/log(n)^sqrt(n).

Original entry on oeis.org

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

Views

Author

Bernard Schott, Aug 10 2020

Keywords

Comments

The series u(n) = sqrt(n)^log(n)/log(n)^sqrt(n) is convergent because n^2 * u(n) -> 0 when n -> oo.

Examples

			32.219419584243365152435936117722884...
		

References

  • J. Moisan & A. Vernotte, Analyse, Topologie et Séries, Exercices corrigés de Mathématiques Spéciales, Ellipses, 1991, Exercice B-1 a-3 pp. 70, 87-88.

Crossrefs

Programs

  • Maple
    evalf(sum(sqrt(n)^log(n)/log(n)^sqrt(n), n=2..infinity), 120);
  • PARI
    default(realprecision, 100); sumpos(n=2, sqrt(n)^log(n)/log(n)^sqrt(n)) \\ Michel Marcus, Aug 10 2020

Formula

Equals Sum_{n>=2} sqrt(n)^log(n)/log(n)^sqrt(n).

Extensions

a(37)-a(101) from Robert Price, Aug 21 2020
Showing 1-7 of 7 results.