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 A147977 #16 Aug 21 2021 13:06:35
%S A147977 -4,-9,-19,-9,317,3351,26141,183111,1216637,7842231,49591901,
%T A147977 309595431,1915328957,11771279511,71987413661,438579282951,
%U A147977 2664183937277,16146410851191,97676152243421,590010212989671,3559688008961597
%N A147977 a(n) = 6^n-5^n-4^n-3^n-2^n-1.
%H A147977 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (21,-175,735,-1624,1764,-720).
%F A147977 G.f.: x*(1524*x^5-2700*x^4+1755*x^3-530*x^2+75*x-4)/((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)). [_Colin Barker_, Oct 29 2012]
%t A147977 lst={};Do[p=6^n-5^n-4^n-3^n-2^n-1^n;AppendTo[lst,p],{n,0,5!}];lst
%t A147977 Table[6^n-5^n-4^n-3^n-2^n-1,{n,0,20}] (* or *) LinearRecurrence[{21,-175,735,-1624,1764,-720},{-4,-9,-19,-9,317,3351},30] (* _Harvey P. Dale_, Jan 17 2017 *)
%Y A147977 Cf. A147975, A147976, A147978, A147979.
%K A147977 sign,easy
%O A147977 1,1
%A A147977 _Vladimir Joseph Stephan Orlovsky_, Nov 18 2008