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 A373644 #8 Jun 12 2024 08:22:10
%S A373644 1,1,1,1,2,4,6,8,11,18,29,44,64,96,148,228,345,519,786,1198,1824,2766,
%T A373644 4190,6358,9661,14674,22268,33786,51284,77866,118212,179426,272333,
%U A373644 413391,627547,952613,1445995,2194911,3331793,5057593,7677250,11653681,17689720
%N A373644 a(n) = Sum_{k=0..floor(n/4)} binomial(2*n-7*k,k).
%H A373644 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,2,0,0,0,-1).
%F A373644 G.f.: 1 / (1 - x^4 - x/(1 - x^4)).
%F A373644 a(n) = a(n-1) + 2*a(n-4) - a(n-8) for n > 7.
%o A373644 (PARI) a(n) = sum(k=0, n\4, binomial(2*n-7*k, k));
%Y A373644 Cf. A052535, A122367, A373639.
%K A373644 nonn,easy
%O A373644 0,5
%A A373644 _Seiichi Manyama_, Jun 12 2024