(MAGMAMagma) [Numerator((&+[(-1)^k*Factorial(n)*(16/25)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 17 2018
(MAGMAMagma) [Numerator((&+[(-1)^k*Factorial(n)*(16/25)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 17 2018
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seq(coeff(series(factorial(n)*exp(16*x-625*x^2), x, n+1), x, n), n=0..15); # Muniru A Asiru, Jul 17 2018
(GAP) List(List([0..15], n->Sum([0..Int(n/2)], k->(-1)^k*Factorial(n)*(16/25)^(n-2*k)/(Factorial(k)*Factorial(n-2*k)))), NumeratorRat); # Muniru A Asiru, Jul 17 2018
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G. C. Greubel, <a href="/A160012/b160012.txt">Table of n, a(n) for n = 0..380</a>
From G. C. Greubel, Jul 17 2018: (Start)
a(n) = 25^n * Hermite(n, 8/25).
E.g.f.: exp(16*x - 625*x^2).
a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(16/25)^(n-2*k)/(k!*(n-2*k)!)). (End)
Table[25^n*HermiteH[n, 8/25], {n, 0, 30}] (* G. C. Greubel, Jul 17 2018 *)
(PARI) x='x+O('x^30); Vec(serlaplace(exp(16*x - 625*x^2))) \\ G. C. Greubel, Jul 17 2018
(MAGMA) [Numerator((&+[(-1)^k*Factorial(n)*(16/25)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // G. C. Greubel, Jul 17 2018
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(PARI) a(n)=numerator(polhermite(n, 8/25)) \\ Charles R Greathouse IV, Jan 29 2016
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Numerators of 1, 16/25, -994/625, -55904/15625, 2833036/390625
The denominators are an easily recognizable sequence.
Cf. A009969 (denominators).
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