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 A370720 #33 Mar 27 2024 08:53:48
%S A370720 1,4,14,56,241,1088,5082,24352,119036,591224,2975150,15136036,
%T A370720 77721311,402276364,2096572304,10993229392,57951531087,306954017592,
%U A370720 1632807888084,8719002979360,46720890435026,251149205370864,1353974197346154,7318852828505148
%N A370720 G.f. A(x) satisfies A(x) = (1 + x*A(x)^(3/4) / (1+x))^4.
%F A370720 a(n) = 4 * Sum_{k=0..n} (-1)^(n-k) * binomial(n-1,n-k) * binomial(3*k+4,k)/(3*k+4).
%o A370720 (PARI) a(n) = 4*sum(k=0, n, (-1)^(n-k)*binomial(n-1, n-k)*binomial(3*k+4, k)/(3*k+4));
%Y A370720 Cf. A127897, A371494, A371542.
%Y A370720 Cf. A371496.
%K A370720 nonn
%O A370720 0,2
%A A370720 _Seiichi Manyama_, Mar 27 2024