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A158727
a(n) = Hermite(n, 21).
1
1, 42, 1762, 73836, 3090540, 129211992, 5395998264, 225081383184, 9377874118032, 390269410826400, 16222513520584224, 673540179648009408, 27931792247763542208, 1156970310094516546944, 47866526425527842874240
OFFSET
0,2
COMMENTS
The first negative term is a(235). - Georg Fischer, Feb 16 2019
LINKS
FORMULA
From G. C. Greubel, Jul 13 2018: (Start)
E.g.f.: exp(42*x - x^2).
a(n) = 42*a(n-1) - 2*(n-1)*a(n-2). (End)
MATHEMATICA
Table[HermiteH[n, 21], {n, 0, 50}] (* or *) With[{nmax = 50}, CoefficientList[Series[Exp[42*x - x^2], {x, 0, nmax}], x]*Range[0, nmax]!] (* G. C. Greubel, Jul 13 2018 *)
PROG
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Exp(42*x - x^2))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Jul 13 2018
(PARI) x='x+O('x^30); Vec(serlaplace(exp(42*x - x^2))) \\ G. C. Greubel, Jul 13 2018
(PARI) for(n=0, 30, print1(polhermite(n, 21), ", ")) \\ G. C. Greubel, Jul 13 2018
CROSSREFS
Sequence in context: A170723 A170761 A218744 * A208779 A208500 A207588
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Nov 11 2009
STATUS
approved