fibonacci sequence python recursion code example

Example 1: python recursive fibonacci function

# Python program to display the Fibonacci sequence

def recur_fibo(n):
   if n <= 1:
       return n
   else:
       return(recur_fibo(n-1) + recur_fibo(n-2))

nterms = 10

# 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))

Example 2: fibonacci sequence python

# WARNING: this program assumes the
# fibonacci sequence starts at 1
def fib(num):
	"""return the number at index `num` in the fibonacci sequence"""
    if num <= 2:
        return 1
    return fib(num - 1) + fib(num - 2)

# method 2: use `for` loop
def fib2(num):
	a, b = 1, 1
	for _ in range(num - 1):
		a, b = b, a + b
	return a


print(fib(6))  # 8
print(fib2(6))  # same result, but much faster

Example 3: fibonacci sequence python

num = 1
num1 = 0
num2 = 1
import time
for i in range(0, 10):
    print(num)
    num = num1 + num2
    num1 = num2
    num2 = num
    time.sleep(1)

Example 4: code fibonacci python

# Program to display the Fibonacci sequence forever

def fibonacci(i,j):
  print(i;fibonacci(j,i+j))
fibonacci(1,1)