fibonacci no in python code example

Example 1: 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 2: fibonacci sequence python

# This program also assumes the fibonacci sequence starts at 1 
# This code will print as many digits as the user wishes
# Instead of printing a specific number in the sequence 
def fibonacci(digits):

    digit1, digit2 = 1, 1
    amount_of_digits = 0 
    print(str(digit1) + ", " + str(digit2) + ', ', end='')

    while amount_of_digits != digits:
        digit1, digit2 = digit2, digit1 + digit2 
        print(str(digit2) + ", ", end='') # we want to print on the same line
        amount_of_digits = amount_of_digits + 1 

        if amount_of_digits == digits:
            print('\n') 
            print('Loop done.')
            break

fibonacci(10) # this will print the first 10 digits in the sequence