fibonacci sequence python non recursive code example

Example 1: how to create fibonacci sequence in python

#Python program to generate Fibonacci series until 'n' value
n = int(input("Enter the value of 'n': "))
a = 0
b = 1
sum = 0
count = 1
print("Fibonacci Series: ", end = " ")
while(count <= n):
  print(sum, end = " ")
  count += 1
  a = b
  b = sum
  sum = a + b

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)


print(fib(6))  # 8

Example 3: fibonacci recursive python

#fibonacci sequence with memory to increase the speed.
class recur_fibo:
    memory = {0: 1, 1:1}
    
    def fibonacci(n):
        if n in recur_fibo.memory:
            return recur_fibo.memory[n]
        else:
            recur_fibo.memory[n] = recur_fibo.fibonacci(n-1) + recur_fibo.fibonacci(n-2)
            return recur_fibo.memory[n]

if __name__ == "__main__":
    value = recur_fibo.fibonacci(200)
    print(value)