Question: 
Write a function to find the n’th carol number.


Model's Code:
def get_carol(n):
    if n == 1:
        return 1
    elif n == 2:
        return 7
    else:
        return 2 * get_carol(n - 1) + get_carol(n - 2) + 1



Sample Correct Code:
def get_carol(n): 
	result = (2**n) - 1
	return result * result - 2


Asserts:
assert get_carol(2) == 7
assert get_carol(4) == 223
assert get_carol(5) == 959


Tests:
Test 1 of 3: PASS
Test 2 of 3: FAIL: AssertionError()

Test 360 of 974: 260/360 (72.22222222222221%): failed