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 A304444 #15 Oct 03 2023 09:41:58
%S A304444 1,2,14,98,726,5512,42614,333608,2636326,20985272,168012824,
%T A304444 1351507830,10914317934,88432329546,718545161208,5852747363518,
%U A304444 47774241056710,390702055798978,3200542803221192,26257321971526646,215705170816632376,1774181109262878848
%N A304444 Coefficient of x^n in Product_{k>=1} 1/(1-x^k)^(2*n).
%H A304444 Vaclav Kotesovec, <a href="/A304444/b304444.txt">Table of n, a(n) for n = 0..1000</a>
%F A304444 a(n) ~ c * d^n / sqrt(n), where d = 8.42516721063251541777601555584151410936132980324698494327338254953123205... and c = 0.29923152009652750283923119244187982714171590056794904644563876...
%t A304444 nmax = 25; Table[SeriesCoefficient[Product[1/(1-x^k)^(2*n), {k, 1, n}], {x, 0, n}], {n, 0, nmax}]
%t A304444 nmax = 25; Table[SeriesCoefficient[1/QPochhammer[x]^(2*n), {x, 0, n}], {n, 0, nmax}]
%t A304444 (* Calculation of constants {d,c}: *) eq = FindRoot[{1/QPochhammer[r*s]^2 == s, 1/s + 2*r*Sqrt[s]*Derivative[0, 1][QPochhammer][r*s, r*s] == (2*(Log[1 - r*s] + QPolyGamma[0, 1, r*s]))/(s* Log[r*s])}, {r, 1/8}, {s, 2}, WorkingPrecision -> 1000]; {N[1/r /. eq, 120], val = Sqrt[((1 - r*s)*Log[r*s]^2)/(Pi*(16*r*s*ArcTanh[1 - 2*r*s] - (-1 + r*s)*(Log[r*s] - 2*Log[1 - r*s])*(3*Log[r*s] - 2*Log[1 - r*s]) - 8*Log[1 - r*s] - 8*(-1 + r*s)*(-1 + 2*ArcTanh[1 - 2*r*s])* QPolyGamma[0, 1, r*s] + (4 - 4*r*s)* QPolyGamma[0, 1, r*s]^2 + 4*(-1 + r*s)*(QPolyGamma[1, 1, r*s] + r*s*Log[r*s] * (r*s^(3/2)*Log[r*s]* Derivative[0, 2][QPochhammer][r*s, r*s] - 2*Derivative[0, 0, 1][QPolyGamma][0, 1, r*s]))))] /. eq; N[Chop[val], -Floor[Log[10, Abs[Im[val]]]] - 3]} (* _Vaclav Kotesovec_, Oct 03 2023 *)
%Y A304444 Cf. A000712, A008485, A161870, A171803, A304443.
%K A304444 nonn
%O A304444 0,2
%A A304444 _Vaclav Kotesovec_, May 12 2018