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.
%I A159197 #12 Sep 08 2022 08:45:43
%S A159197 1,4,-146,-1880,63436,1471984,-45495224,-1612749344,45140586640,
%T A159197 2270685496384,-56732233335584,-3905439437484416,85475082054073024,
%U A159197 7934074594685996800,-148274224427133801344,-18587578078456375947776,285956053044109633474816
%N A159197 Numerator of Hermite(n, 2/9).
%H A159197 G. C. Greubel, <a href="/A159197/b159197.txt">Table of n, a(n) for n = 0..450</a>
%F A159197 From _G. C. Greubel_, Jun 10 2018: (Start)
%F A159197 a(n) = 9^n * Hermite(n,2/9).
%F A159197 E.g.f.: exp(4*x-81*x^2).
%F A159197 a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(4/9)^(n-2*k)/(k!*(n-2*k)!)). (End)
%t A159197 Numerator[Table[HermiteH[n,2/9],{n,0,50}]] (* _Vladimir Joseph Stephan Orlovsky_, Apr 01 2011*)
%o A159197 (PARI) a(n)=numerator(polhermite(n,2/9)) \\ _Charles R Greathouse IV_, Jan 29 2016
%o A159197 (Magma) [Numerator((&+[(-1)^k*Factorial(n)*(4/9)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // _G. C. Greubel_, Jun 10 2018
%Y A159197 Cf. A159030.
%K A159197 sign,frac
%O A159197 0,2
%A A159197 _N. J. A. Sloane_, Nov 12 2009