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 A387344 #16 Aug 28 2025 00:39:18
%S A387344 1,28,490,6888,85134,966504,10329396,105520272,1040821782,9982940968,
%T A387344 93584478988,860746864432,7790240975244,69539700514704,
%U A387344 613370153844456,5353909699803168,46303471415495910,397188087484393128,3382162609845269404,28610626973414978800
%N A387344 Expansion of 1/(1 - 8*x + 4*x^2)^(7/2).
%H A387344 Vincenzo Librandi, <a href="/A387344/b387344.txt">Table of n, a(n) for n = 0..800</a>
%F A387344 n*a(n) = 4*(2*n+5)*a(n-1) - 4*(n+5)*a(n-2) for n > 1.
%F A387344 a(n) = (binomial(n+6,3)/20) * A387340(n).
%F A387344 a(n) = (-1)^n * Sum_{k=0..n} (1/2)^(n-4*k) * binomial(-7/2,k) * binomial(k,n-k).
%t A387344 CoefficientList[Series[1/(1-8*x+4*x^2)^(7/2),{x,0,33}],x] (* _Vincenzo Librandi_, Aug 28 2025 *)
%o A387344 (PARI) my(N=20, x='x+O('x^N)); Vec(1/(1-8*x+4*x^2)^(7/2))
%o A387344 (Magma) R<x> := PowerSeriesRing(Rationals(), 34); f := 1/(1 - 8*x + 4*x^2)^(7/2); coeffs := [ Coefficient(f, n) : n in [0..33] ]; coeffs; // _Vincenzo Librandi_, Aug 28 2025
%Y A387344 Cf. A387340.
%K A387344 nonn,new
%O A387344 0,2
%A A387344 _Seiichi Manyama_, Aug 27 2025