OFFSET
0,9
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..1325 (first 51 antidiagonals)
FORMULA
For k > 0, e.g.f. of column k: exp((exp(x) - 1)^k).
T(0,k) = 1; T(n,k) = k! * Sum_{j=1..n} binomial(n-1,j-1) * Stirling2(j,k) * T(n-j,k).
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, ...
0, 1, 0, 0, 0, 0, ...
0, 2, 2, 0, 0, 0, ...
0, 5, 6, 6, 0, 0, ...
0, 15, 26, 36, 24, 0, ...
0, 52, 150, 150, 240, 120, ...
PROG
(PARI) T(n, k) = sum(j=0, n, (k*j)!*stirling(n, k*j, 2)/j!);
(PARI) T(n, k) = if(k==0, 0^n, n!*polcoef(exp((exp(x+x*O(x^n))-1)^k), n));
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Oct 17 2022
STATUS
approved