login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A158969
Numerator of Hermite(n, 5/6).
1
1, 5, 7, -145, -1103, 4925, 123895, 87575, -15172895, -88475275, 2015632615, 26003712575, -269076694895, -6962185390675, 28153019652055, 1895235816710375, 1874863777497025, -536453596325102875, -3255976297539604025, 157531083721635311375, 1901199312366721133425
OFFSET
0,2
LINKS
DLMF, Digital library of mathematical functions, Table 18.9.1 for H_n(x).
FORMULA
From G. C. Greubel, Jul 14 2018: (Start)
a(n) = 3^n * Hermite(n, 5/6).
E.g.f.: exp(5*x - 9*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(5/3)^(n-2*k)/(k!*(n-2*k)!)). (End)
D-finite with recurrence a(n) -5*a(n-1) +18*(n-1)*a(n-2)=0. - [DLMF] Georg Fischer, Feb 06 2021
MATHEMATICA
Numerator[Table[HermiteH[n, 5/6], {n, 0, 50}]] (* Vladimir Joseph Stephan Orlovsky, Apr 01 2011*)
Table[3^n*HermiteH[n, 5/6], {n, 0, 30}] (* G. C. Greubel, Jul 14 2018 *)
PROG
(PARI) a(n)=numerator(polhermite(n, 5/6)) \\ Charles R Greathouse IV, Jan 29 2016
(PARI) x='x+O('x^30); Vec(serlaplace(exp(5*x - 9*x^2))) \\ G. C. Greubel, Jul 14 2018
(Magma) [Numerator((&+[(-1)^k*Factorial(n)*(5/3)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 14 2018
CROSSREFS
Cf. A158968.
Sequence in context: A065927 A217726 A016054 * A083842 A164372 A318088
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, Nov 12 2009
STATUS
approved