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 A293707 #29 Dec 22 2018 07:50:27
%S A293707 2,84,137664,14784353280,159433923516825600,
%T A293707 247133428169618164285440000,74871582187843476288006745227264000000,
%U A293707 5793842294883032778309293201687815335916339200000000,145059336151890972759838967800541420103566785450351578316800000000000
%N A293707 Permanent of a Hankel matrix with factorial elements.
%H A293707 Vaclav Kotesovec, <a href="/A293707/b293707.txt">Table of n, a(n) for n = 1..28</a>
%t A293707 Table[Permanent[Table[(i + j)!, {i, 1, n}, {j, 1, n}]], {n, 1, 15}]
%o A293707 (PARI) {a(n) = matpermanent(matrix(n, n, i, j, (i+j)!))}
%o A293707 for(n=1, 10, print1(a(n), ", ")) \\ _Vaclav Kotesovec_, Dec 21 2018
%Y A293707 Cf. A108078.
%K A293707 nonn
%O A293707 1,1
%A A293707 _Vaclav Kotesovec_, Apr 17 2018