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 A309043 #6 Jul 09 2019 11:12:36
%S A309043 1,2,5,6,12,14,23,22,35,36,56,52,77,74,105,90,124,114,163,142,199,184,
%T A309043 256,216,289,258,357,302,404,358,479,390,499,428,576,476,629,554,745,
%U A309043 610,788,682,923,766,1007,880,1168,944,1193,1010,1341,1094,1420,1230,1631,1318,1667
%N A309043 Expansion of Product_{k>=0} (1 + x^(2^k) + x^(2^(k+1)))^2.
%F A309043 G.f.: Product_{k>=0} ((1 - x^(3*2^k))/(1 - x^(2^k)))^2.
%F A309043 G.f. A(x) satisfies: A(x) = (1 + x + x^2)^2 * A(x^2).
%F A309043 a(n) = Sum_{k=0..n} A002487(k+1)*A002487(n-k+1).
%t A309043 nmax = 56; CoefficientList[Series[Product[(1 + x^(2^k) + x^(2^(k + 1)))^2, {k, 0, Floor[Log[2, nmax]] + 1}], {x, 0, nmax}], x]
%t A309043 nmax = 56; A[_] = 1; Do[A[x_] = (1 + x + x^2)^2 A[x^2] + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]
%Y A309043 Cf. A002487, A073469, A171238, A185954, A309044.
%K A309043 nonn
%O A309043 0,2
%A A309043 _Ilya Gutkovskiy_, Jul 09 2019