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 A198767 #16 Sep 08 2022 08:46:00
%S A198767 7,39,199,999,4999,24999,124999,624999,3124999,15624999,78124999,
%T A198767 390624999,1953124999,9765624999,48828124999,244140624999,
%U A198767 1220703124999,6103515624999,30517578124999,152587890624999,762939453124999
%N A198767 8*5^n-1.
%H A198767 Vincenzo Librandi, <a href="/A198767/b198767.txt">Table of n, a(n) for n = 0..1000</a>
%H A198767 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (6,-5).
%F A198767 a(n) = 5*a(n-1)+4.
%F A198767 a(n) = 6*a(n-1)-5*a(n-2), n>1.
%F A198767 G.f.: (7 - 3*x)/(1 - 6*x + 5*x^2). - _Vincenzo Librandi_, Jan 04 2013
%t A198767 CoefficientList[Series[(7 - 3*x)/(1 - 6*x + 5*x^2), {x, 0, 30}], x] (* _Vincenzo Librandi_, Jan 04 2013 *)
%o A198767 (Magma) [8*5^n-1: n in [0..30]];
%Y A198767 Cf. A024049, A057651, A081655.
%K A198767 nonn,easy
%O A198767 0,1
%A A198767 _Vincenzo Librandi_, Oct 30 2011