OFFSET
0,4
FORMULA
T(n, k) = [T^-2](n-1, k) - [T^-2](n-1, k-1) for n>k>0, with T(n, n)=1 for n>=0 and T(n, 0) = [T^-2](n-1, 0) for n>0.
EXAMPLE
Rows of matrix T begin:
[1],
[1,1],
[ -2,3,1],
[13,-19,7,1],
[ -209,310,-115,15,1],
[7558,-11328,4315,-575,31,1],
[ -584837,883178,-342761,46965,-2607,63,1],
[94047241,-142845383,56217824,-7856782,448173,-11199,127,1],...
and is formed from the first differences of the rows
of the inverse matrix square, T^(-2):
[1],
[ -2,1],
[13,-6,1],
[ -209,101,-14,1],
[7558,-3770,545,-30,1],
[ -584837,298341,-44420,2545,-62,1],...
PROG
(PARI) {T(n, k)=local(A=Mat(1), B); for(m=2, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, if(j==1, B[i, j]=(A^-2)[i-1, 1], B[i, j]=(A^-2)[i-1, j]-(A^-2)[i-1, j-1])); )); A=B); return(A[n+1, k+1])}
CROSSREFS
KEYWORD
sign,tabl
AUTHOR
Paul D. Hanna, Jan 22 2005
STATUS
approved