OFFSET
0,8
COMMENTS
FORMULA
T(n,k) = 0 if k < 0 or k > n.
T(n,k) = 1 if k=0 or k=n or n=2.
T(n,k)= (n-k+1)*T(n-1,k-1) + (k+1)*T(n-1,k), n > 2 and 1 <= k < n.
EXAMPLE
Triangle begins
1;
1, 1;
1, 1, 1;
1, 5, 5, 1;
1, 14, 30, 14, 1;
1, 33, 146, 146, 33, 1;
1, 72, 603, 1168, 603, 72, 1;
1, 151, 2241, 7687, 7687, 2241, 151, 1;
1, 310, 7780, 44194, 76870, 44194, 7780, 310, 1;
1, 629, 25820, 231236, 649514, 649514, 231236, 25820, 629, 1;
MAPLE
A188587 := proc(n, k) if k < 0 or k > n then 0; elif k=0 or k= n or n=2 then 1; else (n-k+1)*procname(n-1, k-1)+(k+1)*procname(n-1, k) ; end if; end proc:
seq(seq(A188587(n, k), k=0..n), n=0..10) ; # R. J. Mathar, Apr 13 2011
CROSSREFS
KEYWORD
AUTHOR
Paul Barry, Apr 04 2011
STATUS
approved