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 A269914 #25 Mar 15 2025 09:16:06 %S A269914 1,5,20,71,237,761,2377,7278,21945,65375,192861,564387,1640496, %T A269914 4741103,13634501,39042437,111379025,316687006,897796581,2538530615, %U A269914 7160768785,20156241155,56626360256,158804376883,444638710925,1243115597929,3470779612521,9678320566654 %N A269914 Number of ternary strings of length n with maximal run length two containing 112. %H A269914 Math StackExchange, <a href="http://math.stackexchange.com/questions/1685843">Words built with 0,1,2</a> %H A269914 Marko Riedel, <a href="/A269914/a269914.maple.txt">Maple code by total enumeration and by generating function.</a> %H A269914 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (3,3,-5,-11,-8,-2). %F A269914 G.f.: x^3*(x+1)*(x^2+x+1)/((2*x^2+2*x-1)*(x^4+3*x^3+3*x^2+x-1)). %t A269914 Drop[CoefficientList[Series[x^3 (x + 1) (x^2 + x + 1)/((2 x^2 + 2 x - 1) (x^4 + 3 x^3 + 3 x^2 + x - 1)), {x, 0, 30}], x], 3] (* _Michael De Vlieger_, Mar 08 2016 *) %Y A269914 Cf. A081038, A269915, A269916, A269917. %K A269914 nonn %O A269914 3,2 %A A269914 _Marko Riedel_, Mar 07 2016