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 A199317 #20 Feb 27 2024 13:34:46
%S A199317 3,13,73,433,2593,15553,93313,559873,3359233,20155393,120932353,
%T A199317 725594113,4353564673,26121388033,156728328193,940369969153,
%U A199317 5642219814913,33853318889473,203119913336833,1218719480020993,7312316880125953,43873901280755713
%N A199317 a(n) = 2*6^n + 1.
%H A199317 Vincenzo Librandi, <a href="/A199317/b199317.txt">Table of n, a(n) for n = 0..1000</a>
%H A199317 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (7,-6).
%F A199317 a(n) = 6*a(n-1)-5.
%F A199317 a(n) = 7*a(n-1)-6*a(n-2).
%F A199317 G.f.: (3-8*x)/((1-x)*(1-6*x)).
%F A199317 a(n) = 1 + A167747(n+1) = 1 + 2*A000400(n) = A000400(n) + A062394(n). - _Alois P. Heinz_, Jul 02 2023
%t A199317 2 6^Range[0,30]+1 (* or *) LinearRecurrence[{7,-6},{3,13},30] (* _Harvey P. Dale_, Jul 02 2023 *)
%o A199317 (Magma) [2*6^n+1: n in [0..30]];
%Y A199317 Cf. A000400, A062394, A167747.
%K A199317 nonn,easy
%O A199317 0,1
%A A199317 _Vincenzo Librandi_, Nov 05 2011