OFFSET
1,2
PROG
(PARI) forstep(n=2, 40, 2, s=0; for(k=3, n, s+=(k-1)!*binomial(n, k)/2); print1(s, ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Lambert Klasen (Lambert.Klasen(AT)gmx.net), Nov 16 2004
STATUS
approved