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 A289420 #7 Jul 21 2019 10:03:34
%S A289420 1,13,102,629,3366,16422,75140,328185,1384345,5685306,22863861,
%T A289420 90420110,352754930,1360882980,5201391077,19724548877,74300429926,
%U A289420 278279597781,1037075511926,3848154018734,14224439297732,52402156308977,192466640908913,705003243252722
%N A289420 Number of Dyck paths of semilength n and height exactly 7.
%H A289420 Alois P. Heinz, <a href="/A289420/b289420.txt">Table of n, a(n) for n = 7..1000</a>
%H A289420 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (13,-67,174,-239,166,-50,4).
%F A289420 G.f.: -x^7/((x-1)*(2*x-1)*(2*x^2-4*x+1)*(x^3-9*x^2+6*x-1)).
%t A289420 LinearRecurrence[{13,-67,174,-239,166,-50,4},{1,13,102,629,3366,16422,75140},30] (* _Harvey P. Dale_, Jul 21 2019 *)
%Y A289420 Column k=7 of A080936.
%K A289420 nonn,easy
%O A289420 7,2
%A A289420 _Alois P. Heinz_, Jul 06 2017