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 A367693 #9 Nov 27 2023 06:25:13
%S A367693 1,0,1,0,1,0,1,1,2,2,3,3,4,5,7,9,12,15,19,24,31,40,53,68,88,113,145,
%T A367693 186,241,311,402,519,669,861,1110,1431,1846,2382,3073,3962,5109,6586,
%U A367693 8492,10952,14125,18216,23493,30294,39063,50373,64959,83769,108030,139314
%N A367693 G.f. A(x) satisfies A(x) = 1 / ((1 + x) * (1 - x * A(x^3))).
%F A367693 a(n) = (-1)^n + Sum_{k=0..floor((n-1)/3)} a(k) * a(n-1-3*k).
%o A367693 (PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=(-1)^i+sum(j=0, (i-1)\3, v[j+1]*v[i-3*j])); v;
%Y A367693 Cf. A005043, A351973, A367694.
%Y A367693 Cf. A367659, A367691.
%K A367693 nonn
%O A367693 0,9
%A A367693 _Seiichi Manyama_, Nov 27 2023