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 A308441 #11 May 27 2019 18:42:04
%S A308441 1,1,7,1653,40206186,208933247676473,395488498710726039573053,
%T A308441 415462449496430820816987469491515317,
%U A308441 342970299885886953080843975129290159101335513911582,299220423631045059715652854654572624968209204858890842067137945793201
%N A308441 a(n) = (1/n!) * Sum_{i=n..n^2} b(i) where Sum_{i=n..n^2} b(i) * x^i/i! = (Sum_{i=1..n} binomial(n-1,i-1)*x^i/i!)^n.
%H A308441 Seiichi Manyama, <a href="/A308441/b308441.txt">Table of n, a(n) for n = 0..27</a>
%o A308441 (PARI) {a(n) = sum(i=n, n^2, i!*polcoef(sum(j=1, n, binomial(n-1, j-1)*x^j/j!)^n, i))/n!}
%Y A308441 Cf. A308296, A321666.
%K A308441 nonn
%O A308441 0,3
%A A308441 _Seiichi Manyama_, May 27 2019