OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..450
FORMULA
From G. C. Greubel, Jun 09 2018: (Start)
a(n) = 9^n * Hermite(n, 1/9).
E.g.f.: exp(2*x-81*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(2/9)^(n-2k)/(k!*(n-2k)!)). (End)
MATHEMATICA
Numerator[Table[HermiteH[n, 1/9], {n, 0, 50}]] (* Vladimir Joseph Stephan Orlovsky, Apr 01 2011*)
PROG
(PARI) a(n)=numerator(polhermite(n, 1/9)) \\ Charles R Greathouse IV, Jan 29 2016
(PARI) for(n=0, 30, print1(9^n*polhermite(n, 1/9), ", ")) \\ G. C. Greubel, Jun 10 2018
(Magma) [Numerator((&+[(-1)^k*Factorial(n)*(2/9)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jun 09 2018
CROSSREFS
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, Nov 12 2009
STATUS
approved