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 A383200 #17 May 08 2025 09:59:21
%S A383200 9,74,610,5020,41317,340050,2798709,23034169,189577752,1560278726,
%T A383200 12841536934,105689495131,869854553902,7159149960981,58921836913893,
%U A383200 484943447787706,3991222267830858,32848892512931768,270355712339865433,2225104276073281126,18313239977617203949
%N A383200 Number of positive integers with n digits in which adjacent digits differ by at most 5.
%H A383200 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (8,3,-9,-1,2).
%F A383200 G.f.: -x*(2*x^4-x^3-9*x^2+2*x+9)/((x+1)*(2*x^4-3*x^3-6*x^2+9*x-1)). - _Alois P. Heinz_, Apr 26 2025
%t A383200 Rest[CoefficientList[Series[-x*(2*x^4-x^3-9*x^2+2*x+9)/((x+1)*(2*x^4-3*x^3-6*x^2+9*x-1)),{x,0,21}],x]] (* or *) LinearRecurrence[{8,3,-9,-1,2},{9,74,610,5020,41317},21] (* _James C. McMahon_, May 08 2025 *)
%Y A383200 Cf. A235163, A383197, A383198, A383199, A383201, A383202.
%K A383200 nonn,base,easy
%O A383200 1,1
%A A383200 _Edwin Hermann_, Apr 19 2025
%E A383200 a(11)-a(21) from _Alois P. Heinz_, Apr 26 2025