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 A066387 #31 Feb 05 2019 17:17:46
%S A066387 1,1,2,1,0,6,1,12,0,24,1,0,0,0,120,1,120,360,0,0,720,1,0,0,0,0,0,5040,
%T A066387 1,1680,0,20160,0,0,0,40320,1,0,60480,0,0,0,0,0,362880,1,30240,0,0,
%U A066387 1814400,0,0,0,0,3628800,1,0,0,0,0,0,0,0,0,0,39916800
%N A066387 Triangle T(n,m) (1<=m<=n) giving number of maps f:N -> N such that f^m(X)=X+n for all natural numbers X.
%H A066387 Vincenzo Librandi, <a href="/A066387/b066387.txt">Rows n = 1..100, flattened</a>
%H A066387 A. Heinis, R. Jeurissen and L. Kamstra, <a href="http://www.nieuwarchief.nl/serie5/pdf/naw5-2001-02-2-189.pdf">Problem 18</a> and <a href="http://www.nieuwarchief.nl/serie5/pdf/naw5-2001-02-4-380.pdf">solution</a>, Nieuw Arch. Wisk. 5/2 (2001) 380.
%F A066387 T(n,m) = n!/(n/m)! if m|n, T(n,m) = 0 otherwise.
%e A066387 Triangle T(n,m) begins:
%e A066387 1;
%e A066387 1, 2;
%e A066387 1, 0, 6;
%e A066387 1, 12, 0, 24;
%e A066387 1, 0, 0, 0, 120;
%e A066387 1, 120, 360, 0, 0, 720;
%e A066387 1, 0, 0, 0, 0, 0, 5040;
%e A066387 1, 1680, 0, 20160, 0, 0, 0, 40320;
%e A066387 ...
%t A066387 t[n_, m_] /; Divisible[n, m] := n!/(n/m)!; t[_, _] = 0; Flatten[Table[t[n, m], {n, 1, 11}, {m, 1, n}]] (* _Jean-François Alcover_, Nov 29 2011 *)
%Y A066387 Row sums give A057625.
%Y A066387 Main diagonal gives A000142.
%Y A066387 m-section of column m=2-4 (for n>0) gives: A001813, A064350, A166338.
%K A066387 easy,nonn,tabl,nice
%O A066387 1,3
%A A066387 _Floor van Lamoen_, Dec 23 2001