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 A339984 #7 Dec 26 2020 02:48:19
%S A339984 0,0,0,1,1,3,5,13,26,65,147,369,899,2298,5851,15261,39945,105948,
%T A339984 282504,759480,2052027,5576017,15216998,41705762,114715503,316611401,
%U A339984 876466003,2433091773,6771462322,18889829555,52809592990,147935027381,415182991401,1167251435240
%N A339984 G.f.: g(x) * g(x^2), where g(x) is the g.f. of A000081.
%H A339984 Vaclav Kotesovec, <a href="/A339984/b339984.txt">Table of n, a(n) for n = 0..2000</a>
%F A339984 a(n) ~ A339986 * A051491^n / n^(3/2).
%t A339984 max = 30; A000081 = Rest[Cases[ Import["https://oeis.org/A000081/b000081.txt", "Table"], {_, _}][[All, 2]]]; g81 = Sum[A000081[[k]]*x^k, {k, 1, max}]; g81x2 = Sum[A000081[[k]]*x^(2*k), {k, 1, max}]; CoefficientList[Series[g81 * g81x2, {x, 0, max}], x]
%Y A339984 Cf. A000081, A217781, A309619, A339985.
%K A339984 nonn
%O A339984 0,6
%A A339984 _Vaclav Kotesovec_, Dec 25 2020