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.

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A062138 Coefficient triangle of generalized Laguerre polynomials n!*L(n,5,x)(rising powers of x).

Original entry on oeis.org

1, 6, -1, 42, -14, 1, 336, -168, 24, -1, 3024, -2016, 432, -36, 1, 30240, -25200, 7200, -900, 50, -1, 332640, -332640, 118800, -19800, 1650, -66, 1, 3991680, -4656960, 1995840, -415800, 46200, -2772, 84, -1, 51891840, -69189120
Offset: 0

Views

Author

Wolfdieter Lang, Jun 19 2001

Keywords

Comments

The row polynomials s(n,x) := n!*L(n,5,x)= sum(a(n,m)*x^m,m=0..n) have e.g.f. exp(-z*x/(1-z))/(1-z)^6. They are Sheffer polynomials satisfying the binomial convolution identity s(n,x+y) = sum(binomial(n,k)*s(k,x)*p(n-k,y),k=0..n), with polynomials sum(|A008297(n,m)|*(-x)^m, m=1..n), n >= 1 and p(0,x)=1 (for Sheffer polynomials see A048854 for S. Roman reference).
These polynomials appear in the radial part of the l=2 (d-wave) eigen functions for the discrete energy levels of the H-atom. See Messiah reference.
For m=0..5 the (unsigned) column sequences (without leading zeros) are: A001725(n+5), A062148-A062152. Row sums (signed) give A062191; row sums (unsigned) give A062192.
The unsigned version of this triangle is the triangle of unsigned 3-Lah numbers A143498. - Peter Bala, Aug 25 2008

Examples

			Triangle begins:
  {1};
  {6, -1};
  {42, -14, 1};
  {336, -168, 24, -1};
  ...
2!*L(2, 5, x) = 42-14*x+x^2.
		

References

  • A. Messiah, Quantum mechanics, vol. 1, p. 419, eq.(XI.18a), North Holland, 1969.

Crossrefs

For m=0..5 the (unsigned) column sequences (without leading zeros) are: A001725(n+5), A062148, A062149, A062150, A062151, A062152.
Row sums (signed) give A062191, row sums (unsigned) give A062192.
Cf. A143498.

Programs

  • Mathematica
    Flatten[Table[((-1)^m)*n!*Binomial[n+5,n-m]/m!,{n,0,8},{m,0,n}]] (* Indranil Ghosh, Feb 24 2017 *)
  • PARI
    tabl(nn) = {for (n=0, nn, for (m=0, n, print1(((-1)^m)*n!*binomial(n+5, n-m)/m!, ", "); ); print(); ); } \\ Indranil Ghosh, Feb 24 2017
    
  • PARI
    row(n) = Vecrev(n!*pollaguerre(n, 5)); \\ Michel Marcus, Feb 06 2021
    
  • Python
    import math
    f=math.factorial
    def C(n, r):return f(n)//f(r)//f(n-r)
    i=-1
    for n in range(26):
        for m in range(n+1):
            i += 1
            print(str(i)+" "+str(((-1)**m)*f(n)*C(n+5, n-m)//f(m))) # Indranil Ghosh, Feb 24 2017

Formula

T(n, m) = ((-1)^m)*n!*binomial(n+5, n-m)/m!.
E.g.f. for m-th column: ((-x/(1-x))^m)/(m!*(1-x)^6), m >= 0.

A062151 Fifth column sequence of triangle A062138 (generalized a=5 Laguerre).

Original entry on oeis.org

1, 50, 1650, 46200, 1201200, 30270240, 756756000, 19027008000, 485188704000, 12614906304000, 335556507686400, 9151541118720000, 256243151324160000, 7371918353479680000, 217998157024327680000
Offset: 0

Views

Author

Wolfdieter Lang, Jun 19 2001

Keywords

Examples

			a(2) = (2+4)! * binomial(2+9,9) / 4! = (720 * 55)/ 24 = 1650. - _Indranil Ghosh_, Feb 24 2017
		

Crossrefs

Cf. A062150.

Programs

  • Magma
    [Factorial(n+4)*Binomial(n+9,9)/Factorial(4): n in [0..20]]; // G. C. Greubel, May 12 2018
  • Mathematica
    Table[(n+4)!*Binomial[n+9,9]/4!,{n,0,15}] (* Indranil Ghosh, Feb 24 2017 *)
  • PARI
    a(n) = (n+4)!*binomial(n+9,9)/4! \\ Indranil Ghosh, Feb 24 2017
    
  • Python
    import math
    f=math.factorial
    def C(n, r):return f(n)/f(r)/f(n-r)
    def A062151(n): return f(n+4)*C(n+9, 9)/f(4) # Indranil Ghosh, Feb 24 2017
    

Formula

E.g.f.: (1+36*x+216*x^2+336*x^3+126*x^4)/(1-x)^14.
a(n) = A062138(n+4, 4).
a(n) = (n+4)!*binomial(n+9, 9)/4!.
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-9) = (-1)^(n-1)*f(n,9,-5), (n>=9). - Milan Janjic, Mar 01 2009
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