phone call system

An organization of 100 people wishes to set up a telephone call system. The initial contact person calls three other persons, each of whom calls three others, and so on, until all persons in the organization have been contacted. The maximum number of people who do not need to make a call is? SHOW PROOF

Bugz, we all know that you've seen all of these problems already, so why bother doing them?;)

Well Kalkewl8ter, people wanted questions and i posted a few, but it seems that nobody even attempts them but bugz! Meh what can you do.