hey all,

I'm on my last problem and I'm stuck. I think it is just too late, but i desperately want to finish this today. Anyhow here is what it reads:

In any group of k people, k>=1, each person is to shake hands with every other person. Find a formula for the number of handshakes, and prove the formula using induction.

Once i get the formula the proof is cake, but the formula is driving me crazy, and it is probably very simple.

so here is what I have
Code:
1 person = 0 shakes
2 people = 1 shake
3 people = 3 shakes
P(4) = 6
P(5) = 10
P(6) = 15
...and so on
can anyone put me on the right track?

thanks,

axon