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 A016819 #19 Apr 21 2023 05:46:27
%S A016819 1,78125,4782969,62748517,410338673,1801088541,6103515625,17249876309,
%T A016819 42618442977,94931877133,194754273881,373669453125,678223072849,
%U A016819 1174711139837,1954897493193,3142742836021,4902227890625,7446353252589,11047398519097,16048523266853,22876792454961
%N A016819 a(n) = (4n+1)^7.
%H A016819 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (8,-28,56,-70,56,-28,8,-1).
%F A016819 From _Amiram Eldar_, Apr 21 2023: (Start)
%F A016819 a(n) = A016813(n)^7.
%F A016819 Sum_{n>=0} 1/a(n) = 61*Pi^7/368640 + 127*zeta(7)/256. (End)
%t A016819 Table[(4n+1)^7,{n,0,100}] (* _Mohammad K. Azarian_, Jun 20 2016 *)
%t A016819 LinearRecurrence[{8,-28,56,-70,56,-28,8,-1},{1,78125,4782969,62748517,410338673,1801088541,6103515625,17249876309},20] (* _Harvey P. Dale_, May 25 2022 *)
%Y A016819 Cf. A013665, A016813.
%K A016819 nonn,easy
%O A016819 0,2
%A A016819 _N. J. A. Sloane_