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 A164539 #24 Sep 08 2022 08:45:47
%S A164539 1,13,33,157,545,2189,8193,31709,120769,463501,1772385,6789277,
%T A164539 25985249,99495437,380887617,1458243293,5582699905,21373102861,
%U A164539 81825105057,313261930141,1199299595681,4591432702349,17577962574465,67295954065373
%N A164539 a(n) = 2*a(n-1) + 7*a(n-2) for n > 1; a(0) = 1, a(1) = 13.
%C A164539 Binomial transform of A164675. Inverse binomial transform of A164540.
%C A164539 Pisano period lengths: 1, 1, 8, 1, 24, 8, 3, 2, 24, 24, 15, 8, 168, 3, 24, 2, 4, 24, 120, 24, ... - _R. J. Mathar_, Aug 10 2012
%H A164539 Vincenzo Librandi and Harvey P. Dale, <a href="/A164539/b164539.txt">Table of n, a(n) for n = 0..1000</a> (Vincenzo Librandi to 177)
%H A164539 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,7).
%F A164539 a(n) = 2*a(n-1) + 7*a(n-2) for n > 1; a(0) = 1, a(1) = 13.
%F A164539 G.f.: (1+11*x)/(1-2*x-7*x^2).
%F A164539 a(n) = ((1+3*sqrt(2))*(1+2*sqrt(2))^n + (1-3*sqrt(2))*(1-2*sqrt(2))^n)/2.
%F A164539 a(n) = 11*A015519(n) + A015519(n+1). - _R. J. Mathar_, Aug 10 2012
%t A164539 LinearRecurrence[{2,7},{1,13},50] (* _Harvey P. Dale_, Oct 16 2011 *)
%o A164539 (Magma) Z<x>:=PolynomialRing(Integers()); N<r>:=NumberField(x^2-2); S:=[ ((1+3*r)*(1+2*r)^n+(1-3*r)*(1-2*r)^n)/2: n in [0..23] ]; [ Integers()!S[j]: j in [1..#S] ]; // _Klaus Brockhaus_, Aug 20 2009
%Y A164539 Cf. A164675, A164540.
%K A164539 nonn,easy
%O A164539 0,2
%A A164539 Al Hakanson (hawkuu(AT)gmail.com), Aug 15 2009
%E A164539 Edited and extended beyond a(5) by _Klaus Brockhaus_, Aug 20 2009