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 A164395 #18 Feb 14 2018 21:09:38
%S A164395 1,2,4,8,14,24,42,72,122,208,354,600,1018,1728,2930,4968,8426,14288,
%T A164395 24226,41080,69658,118112,200274,339592,575818,976368,1655554,2807192,
%U A164395 4759930,8071040,13685426,23205288,39347370,66718224,113128802,191823544
%N A164395 Number of binary strings of length n with no substrings equal to 0001 or 0101.
%H A164395 R. H. Hardin, <a href="/A164395/b164395.txt">Table of n, a(n) for n = 0..500</a>
%H A164395 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,2,-2).
%F A164395 a(n) = 2*a(n-1) - a(n-2) + 2*a(n-3) - 2*a(n-4). - _Andrew Howroyd_, Feb 14 2018
%F A164395 G.f.: (1 + x^2)/((1 - x)*(1 - x - 2*x^3)). - _R. J. Mathar_, Dec 01 2011
%t A164395 LinearRecurrence[{2,-1,2,-2}, {1, 2, 4, 8}, 50] (* _G. C. Greubel_, Sep 18 2017 *)
%o A164395 (PARI) Vec((1 + x^2)/((1 - x)*(1 - x - 2*x^3)) + O(x^40)) \\ _G. C. Greubel_, Sep 18 2017
%K A164395 nonn
%O A164395 0,2
%A A164395 _R. H. Hardin_, Aug 14 2009
%E A164395 a(0)-a(3) prepended by _Andrew Howroyd_, Feb 14 2018