Arrgh, here be me code for ye, matey: ``` def fibonacci(n): if n <= 1: return n else: return fibonacci(n-1) + fibonacci(n-2) ``` Now, let's break down the code and talk like pirates, savvy? The function starts with a simple check: if the input `n` is less than or equal to 1, we just return it as the first two numbers in the sequence are 0 and 1. This be called the "base case." ``` if n <= 1: return n ``` But if the input `n` be greater than 1, we have a bit more work to do. We use a recursive call to find the previous two numbers in the sequence by calling the function again with `n-1`. This be called the "recursive case." ``` else: return fibonacci(n-1) + fibonacci(n-2) ``` Now, let's talk like pirates. The first two numbers in the sequence be 0 and 1, just like on the high seas. The next number be 1+1=2, which be like a ship with two masts. Then it be 1+2=3, which be like a ship with three masts. And so on and so forth. ``` 0, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765 ``` So there ye have it, me hearty. The fibonacci sequence be a series of numbers that start with 0 and 1, and each number after that be the sum of the two before it. And if ye ever find yerself lost at sea, just remember: fibonacci be the answer to all yer problems!