#     Python-recursion

# 1. Define the fibonacci function

# 2. Compute fibonacci(20), fibonacci(30) and fibonacci(35)
# 3. Define a recursive function to compute the function f defined by:
#    f(0) = 1
#    f(1) = 7
#    f(n) = n * f(n-2) if n>1
# 4. Define a recursive function to double all the elements of a list of integers
# 5. Define a recursive function to double all the elements of a list of integers until a 0 is found
# 6. Define a recursive function to compute the partial sums of a list of integers
# 7. Define a function to compute the permutations of a list
