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Let's take a look at the Fibonacci sequence.

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A Fibonacci sequence is a series of numbers in which each number is the sum of the two preceding numbers.

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Right.

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So this might be something that you're already familiar with, but let's say we have a function called.

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Um, Fibonacci.

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And then we accept in as the parameter.

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Right.

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So we'll say that we want the Fibonacci of six.

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If the sequence of numbers is the sum of the two preceding numbers?

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Well, we we start out at one and.

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Put zero here for clarity.

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Zero plus one is one.

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Okay, So this is the first number.

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This is the second number.

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One plus one is two.

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So that is our third number.

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One plus two is three.

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That is our fourth number.

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Two plus three is five.

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That is our fifth number and three plus five is eight and that is our six number.

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So we can say the Fibonacci of six is equal.

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To eight.

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So the recursion for this would look something like the Fibonacci of N is equal to n plus.

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The Fibonacci of N minus one.

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Now as an exercise, I would like for you to try to implement the recursion for the Fibonacci sequence,

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and I'll give you a hint.

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You will need base cases.

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And the base cases are is if your number is equal to zero, then return zero.

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And if your number is equal to one, then return one.

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Right.

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So if num equals zero.

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Turn zero and then if numb equals one.

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Return.

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So now take a minute and try to implement this recursive algorithm and check to see how your results

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match up to mine.