### Home > CC4 > Chapter 5 > Lesson 5.2.1 > Problem 5-45

5-45.

Refer to sequences (c) and (i) of problem 5-42. Homework Help ✎

How are these two sequences similar?

The numbers in the sequence in part (e) of problem 5-42 are called

**Fibonacci numbers**. They are named after an Italian mathematician who discovered the sequence while studying how fast rabbits could breed. What is different about this sequence than the other three you discovered?

Notice that all the numbers in (c) are perfect squares.

Notice that 0-18 in (i) are double 0-9 in (c).

Check the sums of pairs of numbers in the sequence.