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 A376649 #14 Oct 01 2024 07:20:34
%S A376649 1,0,0,1,0,0,1,0,0,1,1,0,1,1,0,1,1,0,1,2,1,1,2,1,1,2,1,1,3,3,2,3,3,2,
%T A376649 3,3,2,4,6,5,5,6,5,5,6,5,6,10,11,10,11,11,10,11,11,11,16,21,21,21,22,
%U A376649 21,21,22,22,27,37,42,42,43,43,42,43,44,49,64,79,84,85,86,85,85,87,93,113,143
%N A376649 a(n) = Sum_{k=0..floor(n/3)} binomial(floor(k/3),n-3*k).
%H A376649 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,1,1).
%F A376649 G.f.: (1-x^9)/((1-x^3) * (1-x^9-x^10)) = (1+x^3+x^6)/(1-x^9-x^10).
%F A376649 a(n) = a(n-9) + a(n-10).
%F A376649 a(n) = A017877(n) + A017877(n-3) + A017877(n-6).
%o A376649 (PARI) a(n) = sum(k=0, n\3, binomial(k\3, n-3*k));
%o A376649 (PARI) my(N=90, x='x+O('x^N)); Vec((1+x^3+x^6)/(1-x^9-x^10))
%Y A376649 Cf. A079398, A376650.
%Y A376649 Cf. A017877.
%K A376649 nonn,easy
%O A376649 0,20
%A A376649 _Seiichi Manyama_, Oct 01 2024