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A158960 Numerator of Hermite(n, 1/5). 10
1, 2, -46, -292, 6316, 71032, -1436936, -24183472, 454560656, 10582510112, -183387274976, -5658029605952, 89546942024896, 3573911647620992, -51057689020940416, -2603853531376575232, 33085559702952161536, 2149253944507164508672 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The denominators are 5^n = A000351(n) (conjectured). - M. F. Hasler, Feb 16 2014
LINKS
DLMF Digital library of mathematical functions, Table 18.9.1 for H_n(x)
FORMULA
D-finite with recurrence a(n) -2*a(n-1) +50*(n-1)*a(n-2)=0. [DLMF] - R. J. Mathar, Feb 16 2014
a(n) = (-1)^floor(n/2)*2^ceiling(n/2)*A237987(n). - M. F. Hasler, Feb 16 2014
From G. C. Greubel, Jun 09 2018: (Start)
a(n) = 5^n * Hermite(n,1/5).
E.g.f.: exp(2*x-25*x^2).
a(n) = Sum_{k=0..floor(n/2)} (-1)^k*n!*(2/5)^(n-2k)/(k!*(n-2k)!). (End)
EXAMPLE
Numerators of 1, 2/5, -46/25, -292/125, 6316/625, 71032/3125, -1436936/15625,..
MAPLE
A158960 := proc(n)
orthopoly[H](n, 1/5) ;
numer(%) ;
end proc: # R. J. Mathar, Feb 16 2014
MATHEMATICA
Numerator[Table[HermiteH[n, 1/5], {n, 0, 50}]] (* Vladimir Joseph Stephan Orlovsky, Mar 23 2011*)
PROG
(PARI) A158960 = n->numerator(polhermite(n, 1/5)) \\ M. F. Hasler, Feb 16 2014
(Magma) [Numerator((&+[(-1)^k*Factorial(n)*(2/5)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jun 02 2018
CROSSREFS
Sequence in context: A266016 A071777 A179108 * A281327 A302377 A303098
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, Nov 12 2009
STATUS
approved

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Last modified March 1 16:12 EST 2024. Contains 370442 sequences. (Running on oeis4.)