Math 2602  B1 , B2                                                                         Homework  #3
                                          Due Thursday, January 27, 2005

  Let (a_n) be the sequence in which a₁ = 1 and a_n+1 = a_n + 4n + 3 , for n > 1.

  Prove that  a_n = O(n²) .

  Is  n² = O(a_n) ? , Explain.