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 A016820 #25 Sep 08 2022 08:44:41
%S A016820 1,390625,43046721,815730721,6975757441,37822859361,152587890625,
%T A016820 500246412961,1406408618241,3512479453921,7984925229121,
%U A016820 16815125390625,33232930569601,62259690411361,111429157112001,191707312997281,318644812890625,513798374428641
%N A016820 a(n) = (4*n + 1)^8.
%H A016820 Vincenzo Librandi, <a href="/A016820/b016820.txt">Table of n, a(n) for n = 0..1000</a>
%H A016820 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (9, -36, 84, -126, 126, -84, 36, -9, 1).
%F A016820 a(0) = 1, a(1) = 390625, a(2) = 43046721, a(3) = 815730721, a(4) = 6975757441, a(5) = 37822859361, a(6) = 152587890625, a(7) = 500246412961, a(8) = 1406408618241, a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9). - _Harvey P. Dale_, Jul 11 2013
%F A016820 a(n) = A001016(A016813(n)). - _Michel Marcus_, Jan 23 2017
%p A016820 A016820:=n->(4*n+1)^8: seq(A016820(n), n=0..30); # _Wesley Ivan Hurt_, Jan 22 2017
%t A016820 (4 * Range[0, 20] + 1)^8 (* or *) LinearRecurrence[{9, -36, 84, -126, 126, -84, 36, -9, 1}, {1, 390625, 43046721, 815730721, 6975757441, 37822859361, 152587890625, 500246412961, 1406408618241}, 20] (* _Harvey P. Dale_, Jul 11 2013 *)
%o A016820 (Magma) [(4*n+1)^8: n in [0..20]]; // _Vincenzo Librandi_, Aug 28 2017
%Y A016820 Cf. A001016, A016813, A016814.
%K A016820 nonn,easy
%O A016820 0,2
%A A016820 _N. J. A. Sloane_