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 A260639 #10 Nov 22 2015 15:17:02
%S A260639 1,4,206,433284,131782705528,21826979750768842816,
%T A260639 7637711141088259236341772556400,
%U A260639 22237835372502772582455643527946875785037270496,2138255561398515897400115384129197209090292453675665760256378885504
%N A260639 Permanent of the symmetric n X n matrix in A260638.
%H A260639 Wikipedia, <a href="https://en.wikipedia.org/wiki/Permanent">Permanent</a>
%t A260639 Permanent[m_List] := With[{v = Array[x, Length[m]]}, Coefficient[Times @@ (m.v), Times @@ v]]; Table[m = Table[QBinomial[r + c, r, 2], {r, 0, n}, {c, 0, n}]; Permanent[m], {n, 0, 8}]
%Y A260639 Cf. A260638.
%K A260639 nonn
%O A260639 1,2
%A A260639 _Arkadiusz Wesolowski_, Nov 11 2015