Ackermann Function

arr = numpy.zeros(shape=(6, 6))
arr.flags.writeable = True

def wrapper(m, n):
    memoized_ackermann(m, n)

def memoized_ackermann(m, n):
    print (arr)
    if arr[n, m] == 0:
        if m == 0:
            arr[m, n] = n + 1
        elif n == 0:
            memoized_ackermann(m - 1, 1)
            arr[m, 0] = arr[m - 1, 1]
        else:
            memoized_ackermann(m, n-1)
            memoized_ackermann(m-1, arr[m, n-1])
            arr[m,n] = arr[m-1, arr[m, n-1]]

wrapper(4, 5)