Fibonacci corrections

[dazza-codes]

In https://github.com/jmportilla/Python-for-Algorithms--Data-Structures--and-Interviews/blob/master/Recursion/Recursion%20Interview%20Problems/Recursion%20Problems/Recursion%20Problem%203%20-%20Fibonacci%20Sequence.ipynb

The results for the Nth number in the sequence are not clear, unless the start of the sequence begins with the Nth number of 0, i.e.

N=0, 0
N=1, 1
N=2, 1
N=3, 2
N=4, 3
N=5, 5
N=6, 8
N=7, 13
N=8, 21
N=9, 34
N=10, 55
etc.

The description seems to confuse the Fibonacci sequence with a factorial sequence, when it says:

Remember that a fibonacci sequence: 0,1,1,2,3,5,8,13,21,... starts off with a
base case checking to see if n = 0 or 1, then it returns 1.

Else it returns fib(n-1)+fib(n+2).

This should read:

Remember that a Fibonacci sequence: 0,1,1,2,3,5,8,13,21,... starts off with a
base case checking to see if n = 0 or 1, then it returns n, 
else it returns fib(n-1) + fib(n-2).

• if n = 0 or 1, then it returns n (not 1)
• there is a typo in fib(n-1)+fib(n+2), it should be fib(n-1)+fib(n-2).

Hope this is right and helps to make a correction.

PS, thanks for a great course

[dazza-codes]

Also, the corrections to the commentary apply to the solutions, ie.

https://github.com/jmportilla/Python-for-Algorithms--Data-Structures--and-Interviews/blob/master/Recursion/Recursion%20Interview%20Problems/Recursion%20Problems%20-%20%20SOLUTIONS/Recursion%20Problem%203%20-%20Fibonacci%20Sequence%20-%20SOLUTION.ipynb

[dazza-codes]

@jmportilla - there is a PR to fix this in #14; it has a merge conflict but the change is not very complex and could be fixed on a new PR.