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 A017205 #19 Oct 03 2024 03:48:17
%S A017205 19683,5159780352,794280046581,19683000000000,208728361158759,
%T A017205 1352605460594688,6351461955384057,23762680013799936,
%U A017205 75084686279296875,208215748530929664,520411082988487293,1195092568622310912,2558036924386500591,5159780352000000000,9892530380752880769
%N A017205 a(n) = (9*n + 3)^9.
%H A017205 Vincenzo Librandi, <a href="/A017205/b017205.txt">Table of n, a(n) for n = 0..10000</a>
%H A017205 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (10,-45,120,-210,252,-210,120,-45,10,-1).
%F A017205 From _Amiram Eldar_, Oct 03 2024: (Start)
%F A017205 a(n) = A017197(n)^9 = 3^9 * A016785(n).
%F A017205 Sum_{n>=0} 1/a(n) = 1618*Pi^9/(1098337086315*sqrt(3)) + 9841*zeta(9)/387420489. (End)
%t A017205 Table[(9*n + 3)^9, {n, 0, 20}] (* _Amiram Eldar_, Oct 03 2024 *)
%o A017205 (Magma) [(9*n+3)^9: n in [0..20]]; // _Vincenzo Librandi_, Jul 23 2011
%Y A017205 Cf. A013667, A016785, A017197.
%K A017205 nonn,easy
%O A017205 0,1
%A A017205 _N. J. A. Sloane_