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 A160140 #11 Sep 08 2022 08:45:44 %S A160140 1,26,-782,-96148,920620,584671256,8490132856,-4893960693232, %T A160140 -213893273952368,51521932403096480,4146277783283481376, %U A160140 -643386552071776162624,-83226053442166654536512,9092813725551462723320192,1813879773807164800891373440 %N A160140 Numerator of Hermite(n, 13/27). %H A160140 G. C. Greubel, <a href="/A160140/b160140.txt">Table of n, a(n) for n = 0..376</a> %F A160140 From _G. C. Greubel_, Sep 24 2018: (Start) %F A160140 a(n) = 27^n * Hermite(n, 13/27). %F A160140 E.g.f.: exp(26*x - 729*x^2). %F A160140 a(n) = numerator(Sum_{k=0..floor(n/2)} (-1)^k*n!*(26/27)^(n-2*k)/(k!*(n-2*k)!)). (End) %e A160140 Numerators of 1, 26/27, -782/729, -96148/19683, 920620/531441 %t A160140 Table[27^n*HermiteH[n, 13/27], {n, 0, 30}] (* _G. C. Greubel_, Sep 24 2018 *) %o A160140 (PARI) a(n)=numerator(polhermite(n, 13/27)) \\ _Charles R Greathouse IV_, Jan 29 2016 %o A160140 (PARI) x='x+O('x^30); Vec(serlaplace(exp(26*x - 729*x^2))) \\ _G. C. Greubel_, Sep 24 2018 %o A160140 (Magma) [Numerator((&+[(-1)^k*Factorial(n)*(26/27)^(n-2*k)/( Factorial(k) *Factorial(n-2*k)): k in [0..Floor(n/2)]])): n in [0..30]]; // _G. C. Greubel_, Sep 24 2018 %Y A160140 Cf. A009971 (denominators). %K A160140 sign,frac %O A160140 0,2 %A A160140 _N. J. A. Sloane_, Nov 12 2009