OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..100
DLMF Digital library of mathematical functions, Table 18.9.1 for H_n(x)
FORMULA
D-finite with recurrence a(n) -19*a(n-1) +338*(n-1)*a(n-2)=0. [DLMF] - R. J. Mathar, Feb 16 2014
E.g.f.: exp(-x*(169*x-19)). The conjecture is a consequence. - Robert Israel, Jan 02 2017
From G. C. Greubel, Jun 02 2018: (Start)
a(n) = 13^n * Hermite(n, 19/26).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(19/13)^(n-2*k)/(k!*(n-2*k)!)). (End)
EXAMPLE
Numerator of 1, 19/13, 23/169, -12407/2197, -259055/28561, 11852219/371293,...
MAPLE
MATHEMATICA
f[n_] := HermiteH[n, 19/26]*13^n; Array[f, 17, 0] (* Robert G. Wilson v, Nov 13 2011 *)
HermiteH[Range[0, 30], 19/26]//Numerator (* Harvey P. Dale, Feb 02 2017 *)
PROG
(PARI) a(n)=numerator(polhermite(n, 19/26)) \\ Charles R Greathouse IV, Jan 29 2016
(Magma) [Numerator((&+[(-1)^k*Factorial(n)*(19/13)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 11 2018
CROSSREFS
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, Nov 12 2009
STATUS
approved