Fibonacci Number code example

Example 1: fibbonacci

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811,

Example 2: fibonacci

# Easy fibonacci exercise
# Method #1
def fibonacci(n):
    # 1th: 0
    # 2th: 1
    # 3th: 1 ...
    if n == 1:
        return 0
    elif n == 2:
        return 1
    else:
        return fibonacci(n - 1) + fibonacci(n - 2)

# Method #2
def fibonacci2(n):
    if n == 0: return 0
    n1 = 1
    n2 = 1
    # (1, n - 2) because start by 1, 2, 3... not 0, 1, 1, 2, 3....
    for i in range(1, n - 2):
        n1 += n2
        n2 = n1 - n2
    return n1


print(fibonacci(13))
# return the nth element in the fibonacci sequence

Example 3: fibonacci sequence

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ...

Example 4: fibonacci sequence

def fibonacci(n):
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        return fibonacci(n-1) + fibonacci(n-2)

Example 5: fibinachi

def fib(n):
  lisp = []
  
  for i in range(n):
    if len(lisp) < 3:
      if len(lisp) == 0:
        lisp.append(0)
      else:
        lisp.append(1)
    
    else:
      lisp.append(lisp[len(lisp)-1]+lisp[len(lisp)-2])
  
  return lisp