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.

A160104 Numerator of Hermite(n, 5/27).

Original entry on oeis.org

1, 10, -1358, -42740, 5512492, 304384600, -37142220680, -3034178687600, 348731717384080, 38877977386007200, -4187277821653825760, -608713688504523233600, 61068424818638825202880, 11260738942261526747094400, -1044883534589865025424443520
Offset: 0

Views

Author

N. J. A. Sloane, Nov 12 2009

Keywords

Examples

			Numerators of 1, 10/27, -1358/729, -42740/19683, 5512492/531441..
		

Crossrefs

Cf. A009971 (denominators).

Programs

  • Magma
    [Numerator((&+[(-1)^k*Factorial(n)*(10/27)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 12 2018
  • Mathematica
    Numerator[Table[HermiteH[n, 5/27], {n, 0, 30}]] (* or *) Table[27^n* HermiteH[n, 5/27], {n,0,30}] (* G. C. Greubel, Jul 12 2018 *)
  • PARI
    a(n)=numerator(polhermite(n,5/27)) \\ Charles R Greathouse IV, Jan 29 2016
    

Formula

From G. C. Greubel, Jul 12 2018: (Start)
a(n) = 27^n * Hermite(n, 5/27).
E.g.f.: exp(10*x - 729*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(10/27)^(n-2*k)/(k!*(n-2*k)!)). (End)