OFFSET
0,5
COMMENTS
FORMULA
Number triangle T(n, k)=sum{j=0..floor(n/2), (n/(n-j))(-1)^j*C(n-j, j)*A107230(n-2j, k)} (with T(0, n)=0^n).
EXAMPLE
Triangle begins
1;
1,1;
0,2,1;
0,3,3,1;
0,4,8,4,1;
0,5,15,15,5,1;
CROSSREFS
KEYWORD
AUTHOR
Paul Barry, May 14 2005
STATUS
approved