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 A383151 #18 Apr 23 2025 16:21:30
%S A383151 0,-1,10,36,40,-160,-1152,-4480,-13568,-34560,-74240,-123904,-92160,
%T A383151 425984,2867200,11796480,40763392,128122880,378667008,1070858240,
%U A383151 2928148480,7795113984,20300431360,51900317696,130610626560,324219699200,795206483968,1929715384320
%N A383151 a(n) = Sum_{k=0..n} k^4 * (-1)^k * 3^(n-k) * binomial(n,k).
%H A383151 Vincenzo Librandi, <a href="/A383151/b383151.txt">Table of n, a(n) for n = 0..700</a>
%F A383151 a(n) = 2^(n-4) * (-66*n + 75*n^2 - 18*n^3 + n^4).
%t A383151 Table[Sum[(k^4*(-1)^k*3^(n-k))*Binomial[n,k],{k,0,n}],{n,0,30}] (* _Vincenzo Librandi_, Apr 23 2025 *)
%o A383151 (PARI) a(n) = 2^(n-4)*(-66*n+75*n^2-18*n^3+n^4);
%o A383151 (Magma) [&+[k^4 * (-1)^k * 3^(n-k) * Binomial(n,k): k in [0..n]]: n in [0..29]]; // _Vincenzo Librandi_, Apr 23 2025
%Y A383151 Cf. A001787, A178987, A383150, A383152, A383155.
%K A383151 sign,easy
%O A383151 0,3
%A A383151 _Seiichi Manyama_, Apr 18 2025