evaluating Lagrange polynomial using recursion in python (recursion limit exceeded)

I have the following Lagrange polynomial:

and I am trying to use recursion to solve it, so first I wrote the equation as:

((2*n+1)/(n+1)) * x * P(n,x) – (n/(n+1)) * P(n-1,x)

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and I wrote the following function:

def P(n,x):
    if n == 0:
        return 1
    elif n == 1:
        return x
    else:
        return ((2*n+1)/(n+1)) * x * P(n-1,x) - (n/(n+1)) * P(n-1,x)

but I got the following Error:

Traceback (most recent call last):
  File "C:\Users\hp\Desktop\practical work 7\main.py", line 80, in <module>
    print (P(2,2))
  File "C:\Users\hp\Desktop\practical work 7\main.py", line 78, in P
    return ((2*n+1)/n+1) * x * P(n,x) - (n/(n+1)) * P (n-1,x)
  File "C:\Users\hp\Desktop\practical work 7\main.py", line 78, in P
    return ((2*n+1)/n+1) * x * P(n,x) - (n/(n+1)) * P (n-1,x)
  File "C:\Users\hp\Desktop\practical work 7\main.py", line 78, in P
    return ((2*n+1)/n+1) * x * P(n,x) - (n/(n+1)) * P (n-1,x)
  [Previous line repeated 995 more times]
  File "C:\Users\hp\Desktop\practical work 7\main.py", line 73, in P
    if n == 0:
RecursionError: maximum recursion depth exceeded in comparison

I do not want to increase the number of allowed recursions, unless that is the only way to solve the question

I believe that the equation is wrong, since P(n,x) will always call the function and the function will go to the last return again, and it will keep doing that all the time, I just want to know if I missed something or the Question itself is wrong.

>Solution :

Try this:

def P(n, x):
    if n == 0:
        return 1
    if n == 1:
        return x
    return (2 * n - 1) / n * x * P(n - 1, x) - (n - 1) / n * P(n - 2, x)

Examples:

>>> P(2,3)
13.0
>>> P(3,3)
63.0
>>> P(4,3)
321.0