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 A017200 #22 Jul 08 2025 06:03:35
%S A017200 81,20736,194481,810000,2313441,5308416,10556001,18974736,31640625,
%T A017200 49787136,74805201,108243216,151807041,207360000,276922881,362673936,
%U A017200 466948881,592240896,741200625,916636176
%N A017200 a(n) = (9*n+3)^4.
%H A017200 Vincenzo Librandi, <a href="/A017200/b017200.txt">Table of n, a(n) for n = 0..10000</a>
%H A017200 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1)
%F A017200 a(n) = A000583(A017197(n)). - _Michel Marcus_, Nov 06 2015
%F A017200 a(n) = 81*A016780(n). - _Michel Marcus_, Nov 06 2015
%F A017200 From _Ilya Gutkovskiy_, Jun 16 2016: (Start)
%F A017200 G.f.: 81*(1 + 251*x + 1131*x^2 + 545*x^3 + 16*x^4)/(1 - x)^5.
%F A017200 a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5). (End)
%t A017200 Table[(9n+3)^4,{n,0,100}] (* _Mohammad K. Azarian_, Jun 15 2016 *)
%t A017200 LinearRecurrence[{5,-10,10,-5,1},{81,20736,194481,810000,2313441},20] (* _Harvey P. Dale_, May 26 2023 *)
%o A017200 (Magma) [(9*n+3)^4: n in [0..30]]; // _Vincenzo Librandi_, Jul 23 2011
%Y A017200 Cf. A000583 (n^4), A016780 ((3n+1)^4), A017197 (9n+3).
%K A017200 nonn,easy
%O A017200 0,1
%A A017200 _N. J. A. Sloane_