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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A160088 Numerator of Hermite(n, 2/27).

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%I A160088 #13 Sep 08 2022 08:45:44
%S A160088 1,4,-1442,-17432,6237580,126613744,-44965503224,-1287479045408,
%T A160088 453768009722512,16832227624528960,-5887014913080686624,
%U A160088 -268961938417954983296,93340097422316232142528,5079118464249805316316928,-1748851732685582642764208000
%N A160088 Numerator of Hermite(n, 2/27).
%H A160088 G. C. Greubel, <a href="/A160088/b160088.txt">Table of n, a(n) for n = 0..375</a>
%F A160088 From _G. C. Greubel_, Sep 23 2018: (Start)
%F A160088 a(n) = 27^n * Hermite(n, 2/27).
%F A160088 E.g.f.: exp(4*x - 729*x^2).
%F A160088 a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(4/27)^(n-2*k)/(k!*(n-2*k)!)). (End)
%e A160088 Numerators of 1, 4/27, -1442/729, -17432/19683, 6237580/531441...
%t A160088 Numerator[HermiteH[Range[0,20],2/27]] (* _Harvey P. Dale_, Mar 26 2016 *)
%t A160088 Table[27^n*HermiteH[n, 2/27], {n, 0, 30}] (* _G. C. Greubel_, Sep 23 2018 *)
%o A160088 (PARI) a(n)=numerator(polhermite(n, 2/27)) \\ _Charles R Greathouse IV_, Jan 29 2016
%o A160088 (PARI) x='x+O('x^30); Vec(serlaplace(exp(4*x - 729*x^2))) \\ _G. C. Greubel_, Sep 23 2018
%o A160088 (Magma) [Numerator((&+[(-1)^k*Factorial(n)*(4/27)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // _G. C. Greubel_, Sep 23 2018
%Y A160088 Cf. A009971 (denominators).
%K A160088 sign,frac
%O A160088 0,2
%A A160088 _N. J. A. Sloane_, Nov 12 2009