Display Fibonacci Sequence Using Recursion

A Fibonacci sequence is the integer sequence of 0, 1, 1, 2, 3, 5, 8.... The first two terms are 0 and 1. All other terms are obtained by adding the preceding two terms. This means to say the nth term is the sum of (n-1)th and (n-2)th term.

Source Code

# Python program to display the Fibonacci sequence up to n-th term using recursive functions

def recur_fibo(n):
   """Recursive function to
   print Fibonacci sequence"""
   if n <= 1:
       return n
   else:
       return(recur_fibo(n-1) + recur_fibo(n-2))


# take input from the user
nterms = int(input("How many terms? "))

# check if the number of terms is valid
if nterms <= 0:
   print("Plese enter a positive integer")
else:
   print("Fibonacci sequence:")
   for i in range(nterms):
       print(recur_fibo(i))

Output

How many terms? 10
Fibonacci sequence:
0
1
1
2
3
5
8
13
21
34

 

In this program, we ask the user for the number of terms in the sequence. A recursive function recur_fibo() is used to calculate the nth term of the sequence. We use a for loop to iterate and calculate each term recursively.