Chapter: 8. Recursion

8.1 Fibonacci

Implement a recursive function named fibonacci that takes a number N and returns the N-th fibonacci number. The first two fibonacci numbers are 1 and the rest are the sum of the previous two.

8.2 Factorial

The factorial of a non-negative integer N , denoted N! , is the product of all the positive integer less than or equal to N. The value of 0! is defined as 1.