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 A083302 #16 Sep 08 2022 08:45:10 %S A083302 1,7,65,583,5249,47239,425153,3826375,34437377,309936391,2789427521, %T A083302 25104847687,225943629185,2033492662663,18301433963969, %U A083302 164712905675719,1482416151081473,13341745359733255,120075708237599297 %N A083302 a(n) = (4*9^n + (-1)^n)/5. %C A083302 Binomial transform of A083301. %H A083302 Vincenzo Librandi, <a href="/A083302/b083302.txt">Table of n, a(n) for n = 0..300</a> %H A083302 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (8,9). %F A083302 G.f.: (1-x)/((1-*9x)(1+x)). %F A083302 E.g.f.: (4*exp(9*x) + exp(-x))/5. %o A083302 (Magma) [(4*9^n+(-1)^n)/5: n in [0..25]]; // _Vincenzo Librandi_, Jun 29 2011 %o A083302 (PARI) a(n)=4*9^n\/5 \\ _Charles R Greathouse IV_, Jun 29 2011 %K A083302 easy,nonn %O A083302 0,2 %A A083302 _Paul Barry_, Apr 24 2003