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 A016845 #11 Apr 24 2023 02:54:15
%S A016845 19683,40353607,2357947691,38443359375,322687697779,1801152661463,
%T A016845 7625597484987,26439622160671,78815638671875,208728361158759,
%U A016845 502592611936843,1119130473102767,2334165173090451,4605366583984375,8662995818654939,15633814156853823,27206534396294947
%N A016845 a(n) = (4n+3)^9.
%H A016845 <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 A016845 From _Amiram Eldar_, Apr 24 2023: (Start)
%F A016845 a(n) = A004767(n)^9.
%F A016845 Sum_{n>=0} 1/a(n) = 511*zeta(9)/1024 - 277*Pi^9/16515072. (End)
%t A016845 Table[(4*n + 3)^9, {n, 0, 20}] (* _Amiram Eldar_, Apr 24 2023 *)
%Y A016845 Cf. A004767, A013667.
%K A016845 nonn,easy
%O A016845 0,1
%A A016845 _N. J. A. Sloane_