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 A339712 #18 Apr 25 2021 02:22:43
%S A339712 1,5,28,273,3126,46948,823544,16781441,387421948,10000078446,
%T A339712 285311670612,8916102176891,302875106592254,11112006865913416,
%U A339712 437893890382064056,18446744074783625217,827240261886336764178,39346408075327954053967,1978419655660313589123980
%N A339712 a(n) = Sum_{d|n} d^(d+n/d-1) * binomial(d+n/d-2, d-1).
%F A339712 G.f.: Sum_{k >= 1} (k * x/(1 - k * x^k))^k.
%F A339712 If p is prime, a(p) = 1 + p^p.
%t A339712 a[n_] := DivisorSum[n, #^(# + n/# - 1) * Binomial[# + n/# - 2, # - 1] &]; Array[a, 20] (* _Amiram Eldar_, Apr 25 2021 *)
%o A339712 (PARI) a(n) = sumdiv(n, d, d^(d+n/d-1)*binomial(d+n/d-2, d-1));
%o A339712 (PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=1, N, (k*x/(1-k*x^k))^k))
%Y A339712 Cf. A157019, A157020, A324158, A324159, A338661, A339481, A339482, A343573.
%K A339712 nonn
%O A339712 1,2
%A A339712 _Seiichi Manyama_, Apr 24 2021