Page 42 -
P. 42

From the above, it is then straightforward to compute the first few
                             Fibonacci numbers:

                                               1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, …


                             Example 2.1
                             Write a program for finding the first 20 Fibonacci numbers.


                             Solution: The following program fulfills this task:

                                N=18;
                                F(1)=1;
                                F(2)=1;
                                for k=1:N
                                   F(k+2)=F(k)+F(k+1);
                                end
                                F

                             It should be noted that the value of the different elements of the sequence
                             depends on the values of the initial conditions, as illustrated in Pb. 2.1, which
                             follows.



                             In-Class Exercises

                             Pb. 2.1 Find the first 20 elements of the sequence that obeys the same recur-
                             sion relation as that of the Fibonacci numbers, but with the following initial
                             conditions:


                                                   F(1) = 0.5  and F(2) = 1

                             Pb. 2.2 Find the first 20 elements of the sequence generated by the follow-
                             ing difference equation:

                                               F(k + 3) = F(k) + F(k + 1) + F(k + 2)

                             with the following boundary conditions:


                                               F(1) = 1, F(2) = 2,  and F(3) = 3

                             Why do we need to specify three initial conditions?





                             © 2001 by CRC Press LLC
   37   38   39   40   41   42   43   44   45   46   47