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 A299786 #45 Aug 22 2020 11:08:25
%S A299786 1,1,2,11,73,707,8547,127379,2237804,45511484,1049155214,27060763974,
%T A299786 771662014455,24109614539775,818906748562249,30044648617150066,
%U A299786 1184045057676213763,49883902402848781573,2237286132689496359239,106426356238092171308928,5352031894869594850387969
%N A299786 Expansion of Product_{k>=1} (1 + k^(k-1)*x^k).
%C A299786 This sequence is obtained from the generalized Euler transform in A266964 by taking f(n) = -1, g(n) = (-1) * n^(n-1). - _Seiichi Manyama_, Aug 22 2020
%H A299786 Seiichi Manyama, <a href="/A299786/b299786.txt">Table of n, a(n) for n = 0..387</a>
%F A299786 a(n) ~ n^(n-1) * (1 + exp(-1)/n + (2*exp(-2) + 3*exp(-1)/2)/n^2). - _Vaclav Kotesovec_, Jan 22 2019
%t A299786 nmax = 20; CoefficientList[Series[Product[(1 + k^(k - 1) x^k), {k, 1, nmax}], {x, 0, nmax}], x]
%t A299786 a[n_] := a[n] = If[n == 0, 1, Sum[Sum[(-1)^(k/d + 1) d^(k - k/d + 1), {d, Divisors[k]}] a[n - k], {k, 1, n}]/n]; Table[a[n], {n, 0, 20}]
%o A299786 (PARI) N=40; x='x+O('x^N); Vec(prod(k=1, N, 1+k^(k-1)*x^k)) \\ _Seiichi Manyama_, Aug 22 2020
%Y A299786 Cf. A265949, A266964, A304961, A321387, A323634.
%K A299786 nonn
%O A299786 0,3
%A A299786 _Ilya Gutkovskiy_, Jan 21 2019