OFFSET
0,3
PROG
(PARI) {a(n)=(matrix(n+1, n+1, r, c, if(r>=c, sum(m=0, r-c+1, (-1)^(r-c+1-m)*m^r/m!/(r-c+1-m)!)))^-1)[n+1, 1]}
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, May 01 2005
STATUS
approved