OFFSET
0,6
LINKS
Alois P. Heinz, Rows n = 0..100, flattened
Richard P. Stanley, Parking Functions, 2011.
EXAMPLE
Triangle T(n,k) begins:
00 : 1;
01 : 0, 1;
02 : 0, 0, 2;
03 : 0, 3, 0, 3;
04 : 0, 5, 0, 0, 4;
05 : 0, 7, 8, 0, 0, 5;
06 : 0, 25, 12, 0, 0, 0, 6;
07 : 0, 36, 16, 15, 0, 0, 0, 7;
08 : 0, 81, 20, 21, 0, 0, 0, 0, 8;
09 : 0, 107, 74, 27, 24, 0, 0, 0, 0, 9;
10 : 0, 316, 102, 33, 32, 0, 0, 0, 0, 0, 10;
11 : 0, 427, 222, 39, 40, 35, 0, 0, 0, 0, 0, 11;
12 : 0, 869, 286, 153, 48, 45, 0, 0, 0, 0, 0, 0, 12;
MAPLE
p:= l-> (n-> n!*LinearAlgebra[Determinant](Matrix(n, (i, j)
-> (t->`if`(t<0, 0, l[i]^t/t!))(j-i+1))))(nops(l)):
g:= (n, i, l)-> `if`(i*(i+1)/2<n, 0, `if`(n=0, p(l)*x^
`if`(l=[], 0, l[1]), g(n, i-1, l)+
`if`(i>n, 0, g(n-i, i-1, [i, l[]])))):
T:= n-> (f-> seq(coeff(f, x, i), i=0..n))(g(n$2, [])):
seq(T(n), n=0..16);
MATHEMATICA
p[l_] := With[{n = Length[l]}, n!*Det[Table[Function[t,
If[t < 0, 0, l[[i]]^t/t!]][j - i + 1], {i, n}, {j, n}]]];
g[n_, i_, l_] := If[i(i+1)/2 < n, 0, If[n == 0, p[l]*x^
If[l == {}, 0, l[[1]]], g[n, i - 1, l] +
If[i > n, 0, g[n - i, i - 1, Prepend[l, i]]]]];
T[n_] := If[n == 0, {1}, CoefficientList[g[n, n, {}], x]];
Table[T[n], {n, 0, 16}] // Flatten (* Jean-François Alcover, Aug 20 2021, after Alois P. Heinz *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Alois P. Heinz, Nov 30 2015
STATUS
approved