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 A358410 #13 Aug 30 2023 02:00:56
%S A358410 1,2,3,9,25,130,721,5069,40333,363006,3628801,39917607,479001601,
%T A358410 6227025848,87178291591,1307674408449,20922789888001,355687428461452,
%U A358410 6402373705728001,121645100412461861,2432902008176660217,51090942171749356812,1124000727777607680001
%N A358410 a(n) = Sum_{d|n} (d + n/d - 2)!/(d - 1)!.
%F A358410 G.f.: Sum_{k>0} (k-1)! * (x/(1 - x^k))^k.
%F A358410 If p is prime, a(p) = 1 + (p-1)!.
%t A358410 a[n_] := DivisorSum[n, (# + n/# - 2)!/(# - 1)! &]; Array[a, 23] (* _Amiram Eldar_, Aug 30 2023 *)
%o A358410 (PARI) a(n) = sumdiv(n, d, (d+n/d-2)!/(d-1)!);
%o A358410 (PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=1, N, (k-1)!*(x/(1-x^k))^k))
%Y A358410 Cf. A157019, A358280, A358389.
%K A358410 nonn
%O A358410 1,2
%A A358410 _Seiichi Manyama_, Nov 14 2022