Prove by using the recurrence relation, that s(n,n-1) = - ( n C 2) <------------------That last bit is '' - n choose 2'' cant write it properly on here..

I cant work it out?! is the recurrence relation...

s(n,k) = s(n-1,k-1) - (n-1)s(n-1,k) ??

help please..x..