1. The principle of mathematical induction. A property p(n) that involves an integer n is true for any n 2 0, if the followings are true: 1. p(0) is true. 2. if p(k) is true for any k 2 0, then p(k +1) is true. 2. The principle of mathematical induction (strong form). A property p(n) that involves an integer n is true for any n 2 0, if the followings are true: 1. p(0) is true. 2. if p(0),p(1), p(2), ... , p(k) are true for any k 2 0, then p(k + 1) is true. Given a statement p concerning the integer n, suppose: 1. pis true for some particular integer no- 2. If pis true for some particular integer k 2 ng, then it is true for the next integer k+ 1