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 A360749 #13 Feb 19 2023 09:21:05
%S A360749 1,1,1,1,2,5,10,17,30,64,146,315,649,1386,3164,7381,16931,38649,90406,
%T A360749 217474,527586,1277452,3112371,7705059,19336789,48800634,123617380,
%U A360749 315671212,814711955,2119996540,5545342621,14584694613,38641783669,103158314515
%N A360749 Expansion of Sum_{k>=0} (x * (1 + k*x^3))^k.
%F A360749 a(n) = Sum_{k=0..floor(n/4)} (n-3*k)^k * binomial(n-3*k,k).
%o A360749 (PARI) my(N=40, x='x+O('x^N)); Vec(sum(k=0, N, (x*(1+k*x^3))^k))
%o A360749 (PARI) a(n) = sum(k=0, n\4, (n-3*k)^k*binomial(n-3*k, k));
%Y A360749 Cf. A360592, A360748.
%Y A360749 Cf. A003269, A360731, A360747.
%K A360749 nonn
%O A360749 0,5
%A A360749 _Seiichi Manyama_, Feb 19 2023