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A158968
Numerator of Hermite(n, 1/6).
9
1, 1, -17, -53, 865, 4681, -73169, -578717, 8640577, 91975825, -1307797649, -17863446149, 241080488353, 4099584856537, -52313249418065, -1085408633265389, 13039168709612161, 325636855090044193, -3664348770051277073, -109170689819225595605, 1144036589538311163361
OFFSET
0,3
LINKS
DLMF, Digital library of mathematical functions, Table 18.9.1 for H_n(x).
FORMULA
From G. C. Greubel, Jun 02 2018: (Start)
a(n) = 3^n * Hermite(n, 1/6).
E.g.f.: exp(x - 9*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(1/3)^(n-2*k)/(k!*(n-2*k)!)). (End)
D-finite with recurrence a(n) -a(n-1) +18*(n-1)*a(n-2)=0. - [DLMF] Georg Fischer, Feb 06 2021
MATHEMATICA
Numerator[Table[HermiteH[n, 1/6], {n, 0, 50}]] (* Vladimir Joseph Stephan Orlovsky, Apr 01 2011 *)
Table[3^n*HermiteH[n, 1/6], {n, 0, 50}] (* G. C. Greubel, Jul 10 2018 *)
PROG
(PARI) a(n)=numerator(polhermite(n, 1/6)) \\ Charles R Greathouse IV, Jan 29 2016
(Magma) [Numerator((&+[(-1)^k*Factorial(n)*(1/3)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 10 2018
(SageMath) [3^n*hermite(n, 1/6) for n in range(31)] # G. C. Greubel, Jul 12 2024
CROSSREFS
Sequences with e.g.f = exp(x + q*x^2): this sequence (q=-9), A158954 (q=-4), A362177 (q=-3), A362176 (q=-2), A293604 (q=-1), A000012 (q=0), A047974 (q=1), A115329 (q=2), A293720 (q=4).
Sequence in context: A146397 A146405 A228244 * A072895 A300059 A097059
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, Nov 12 2009
STATUS
approved