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 A165323 #18 Sep 02 2025 22:49:09
%S A165323 1,8,72,712,7496,81864,911944,10263752,116119368,1317149128,
%T A165323 14959895624,170020681416,1932918264136,21978286879688,
%U A165323 249924108049992,2842099476549832,32320548186147656,367554952665320904
%N A165323 a(0)=1, a(1)=8, a(n)=17*a(n-1)-64*a(n-2) for n>1.
%C A165323 a(n)/a(n-1) tends to (17+sqrt(33))/2 = 11.3722813...
%C A165323 For n>=2, a(n) equals 8^n times the permanent of the (2n-2) X (2n-2) tridiagonal matrix with 1/sqrt(8)'s along the main diagonal, and 1's along the superdiagonal and the subdiagonal. - _John M. Campbell_, Jul 08 2011
%H A165323 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (17,-64).
%F A165323 G.f.: (1-9*x)/(1-17*x+64*x^2).
%F A165323 a(n) = Sum_{k=0..n} A165253(n,k)*8^(n-k).
%F A165323 a(n) = ((33-sqrt(33))*(17+sqrt(33))^n+(33+sqrt(33))*(17-sqrt(33))^n)/(66*2^n). - _Klaus Brockhaus_, Sep 28 2009
%t A165323 LinearRecurrence[{17,-64},{1,8},20] (* _Harvey P. Dale_, Jun 08 2018 *)
%Y A165323 Cf. A165253.
%K A165323 nonn,easy,changed
%O A165323 0,2
%A A165323 _Philippe Deléham_, Sep 14 2009