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.

A062144 Sixth (unsigned) column sequence of coefficient triangle A062137 of generalized Laguerre polynomials n!*L(n,3,x).

Original entry on oeis.org

1, 54, 1890, 55440, 1496880, 38918880, 998917920, 25686460800, 667847980800, 17660868825600, 476843458291200, 13178219210956800, 373382877643776000, 10856825211488256000, 324153781314435072000
Offset: 0

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Author

Wolfdieter Lang, Jun 19 2001

Keywords

Examples

			a(2) = (2+5)! * binomial(2+8,8)/ 5! = (5040 * 45) / 120 = 1890. - _Indranil Ghosh_, Feb 24 2017
		

Crossrefs

Cf. A062143.

Programs

  • Magma
    [Factorial(n+5)*Binomial(n+8, 8)/Factorial(5): n in [0..20]]; // G. C. Greubel, May 11 2018
  • Mathematica
    Table[(n+5)!*Binomial[n+8,8]/5!,{n,0,14}] (* Indranil Ghosh, Feb 24 2017 *)
  • PARI
    a(n)=(n+5)!*binomial(n+8, 8)/5! \\ Indranil Ghosh, Feb 24 2017
    
  • Python
    import math
    f=math.factorial
    def C(n, r):return f(n)/f(r)/f(n-r)
    def A062144(n): return f(n+5)*C(n+8, 8)/f(5) # Indranil Ghosh, Feb 24 2017
    

Formula

a(n) = (n+5)!*binomial(n+8, 8)/5!.
E.g.f.: N(3;5, x)/(1-x)^14 with N(3;5, x) := Sum_{k=0..5} A062145(5, k) *x^k = 1 +40*x +280*x^2 +560*x^3 +350*x^4 +56*x^5.
If we define f(n,i,x) = Sum_{k=i..n} Sum_{j=i..k} binomial(k,j)*Stirling1(n,k)*Stirling2(j,i)*x^(k-j) then a(n-5) = (-1)^(n-1)*f(n,5, -9), (n>=5). - Milan Janjic, Mar 01 2009