OFFSET
0,3
LINKS
Wikipedia, Hankel matrix.
EXAMPLE
a(3) = 490614:
5, 14, 42;
14, 42, 132;
42, 132, 429.
MAPLE
with(LinearAlgebra):
C:= proc(n) option remember; binomial(2*n, n)/(n+1) end:
a:= n-> `if`(n=0, 1, Permanent(Matrix(n, (i, j)-> C(i+j+n-2)))):
seq(a(n), n=0..10); # Alois P. Heinz, Dec 20 2023
MATHEMATICA
a[n_]:=If[n==0, 1, Permanent[Table[CatalanNumber[i+j+n], {i, 0, n-1}, {j, 0, n-1}]]]; Array[a, 10, 0]
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefano Spezia, Dec 20 2023
STATUS
approved