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 A385867 #27 Aug 09 2025 08:18:42
%S A385867 1,1,10,2568,32455296,33171803873280,4092783209652289536000,
%T A385867 85191758794180067056209100800000,
%U A385867 398579307845175105508944536142159544320000000,538664594626853888213693114387037430238145253736448000000000,262763300482667111090711396658972748636113942776939213363557171200000000000000
%N A385867 Permanent of n X n matrix A defined by A[i,j] = (i+j-1)! for 1 <= i,j <= n.
%H A385867 Vaclav Kotesovec, <a href="/A385867/b385867.txt">Table of n, a(n) for n = 0..29</a>
%t A385867 Join[{1}, Table[Permanent[Table[(i + j - 1)!, {i, 1, n}, {j, 1, n}]], {n, 1, 10}]]
%o A385867 (PARI) a(n) = {matpermanent(matrix(n, n, i, j, (i + j - 1)!))};
%o A385867 for(n=0, 10, print1(a(n), ", "))
%o A385867 (Python)
%o A385867 from math import factorial
%o A385867 from sympy import Matrix
%o A385867 def A385867(n): return Matrix(n, n, lambda i, j: factorial(i+j+1)).per() if n else 1 # _Chai Wah Wu_, Aug 09 2025
%Y A385867 Cf. A059332.
%K A385867 nonn
%O A385867 0,3
%A A385867 _Vaclav Kotesovec_, Aug 08 2025