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 1-2 of 2 results.

A289216 a(n) = n! * Laguerre(n,-10).

Original entry on oeis.org

1, 11, 142, 2086, 34184, 616120, 12083920, 255749840, 5801633920, 140276126080, 3598075308800, 97512721964800, 2782552712473600, 83347512973644800, 2613606571616819200, 85594543750221568000, 2921314815145299968000, 103704333851191177216000
Offset: 0

Views

Author

Alois P. Heinz, Jun 28 2017

Keywords

Crossrefs

Column k=10 of A289192.

Programs

  • Magma
    m:=25; R:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Exp(10*x/(1-x))/(1-x))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, May 11 2018
  • Maple
    a:= n-> n! * add(binomial(n, i)*10^i/i!, i=0..n):
    seq(a(n), n=0..20);
  • Mathematica
    Table[n!*LaguerreL[n, -10], {n, 0, 20}] (* Indranil Ghosh, Jul 04 2017 *)
  • PARI
    my(x = 'x + O('x^30)); Vec(serlaplace(exp(10*x/(1-x))/(1-x))) \\ Michel Marcus, Jul 04 2017
    
  • PARI
    a(n) = n!*pollaguerre(n, 0, -10); \\ Michel Marcus, Feb 05 2021
    
  • Python
    from mpmath import *
    mp.dps=100
    def a(n): return int(fac(n)*laguerre(n, 0, -10))
    print([a(n) for n in range(21)]) # Indranil Ghosh, Jul 04 2017
    

Formula

E.g.f.: exp(10*x/(1-x))/(1-x).
a(n) = n! * Sum_{i=0..n} 10^i/i! * binomial(n,i).
a(n) = n! * A160587(n)/A160589(n).
a(n) ~ exp(-5 + 2*sqrt(10*n) - n) * n^(n + 1/4) / (2^(3/4)*5^(1/4)) * (1 + 643/(48*sqrt(10*n))). - Vaclav Kotesovec, Nov 13 2017
Sum_{n>=0} a(n) * x^n / (n!)^2 = exp(x) * Sum_{n>=0} 10^n * x^n / (n!)^2. - Ilya Gutkovskiy, Jul 17 2020

A160589 Denominator of Laguerre(n, -10).

Original entry on oeis.org

1, 1, 1, 3, 3, 3, 9, 63, 63, 567, 81, 6237, 1701, 243243, 1702701, 5108103, 5108103, 1772199, 781539759, 14849255421, 14849255421, 311834363841, 3430178002251, 7172190368343, 33811754593617, 236682282155319, 3076869668019147
Offset: 0

Views

Author

N. J. A. Sloane, Nov 14 2009

Keywords

Crossrefs

For numerators see A160587.
Cf. A289216.

Programs

  • Magma
    [Denominator((&+[Binomial(n,k)*(10^k/Factorial(k)): k in [0..n]])): n in [0..30]]; // G. C. Greubel, May 13 2018
  • Mathematica
    Denominator[Table[LaguerreL[n, -10], {n, 0, 50}]] (* G. C. Greubel, May 13 2018 *)
  • PARI
    for(n=0,30, print1(denominator(sum(k=0,n, binomial(n,k)*(10^k/k!))), ", ")) \\ G. C. Greubel, May 13 2018
    
  • PARI
    a(n) = denominator(pollaguerre(n, 0, -10)); \\ Michel Marcus, Feb 05 2021
    
Showing 1-2 of 2 results.