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 A356372 #9 Aug 05 2022 06:18:08
%S A356372 2,16,76,386,1474,7349,26807,121964,487068,2105087,7486505,37278746,
%T A356372 133488216,550615531,2263230587,9856735046,35168418266,160420872009,
%U A356372 573578559659,2582163925152,10333237435638,41122278086361,146621866522577,712999981650663,2702556741014621
%N A356372 a(n) = Sum_{k=1..n} binomial(2*n, k) * A000005(k).
%F A356372 a(n) ~ 2^(2*n-1) * (log(n) + 2*gamma), where gamma is the Euler-Mascheroni constant A001620.
%t A356372 Table[Sum[Binomial[2*n, k]*DivisorSigma[0, k], {k, 1, n}], {n, 1, 30}]
%o A356372 (PARI) a(n) = sum(k=1, n, binomial(2*n, k) * numdiv(k)); \\ _Michel Marcus_, Aug 05 2022
%Y A356372 Cf. A000005, A006218, A160399, A351146.
%K A356372 nonn
%O A356372 1,1
%A A356372 _Vaclav Kotesovec_, Aug 04 2022