It doesn’t take long for the Fibonacci sequence to get really large. This program asks for a stopping number, then loops through those numbers until it gets one of length 1000 digits or more. At only 4782 the Fibonacci number problem is solved.

### Problem:

The Fibonacci sequence is defined by the recurrence relation:

Fn = Fn1 + Fn2, where F1 = 1 and F2 = 1.

Hence the first 12 terms will be:

- F1 = 1
- F2 = 1
- F3 = 2
- F4 = 3
- F5 = 5
- F6 = 8
- F7 = 13
- F8 = 21
- F9 = 34
- F10 = 55
- F11 = 89
- F12 = 144

The 12th term, F12, is the first term to contain three digits.

What is the first term in the Fibonacci sequence to contain 1000 digits?

### One Possible Solution:

def find_fibonacci(n): """Find fibonacci""" a, b = 0, 1 for i in range(0, n): x = str(a) if len(x) == 1000: print a print "F(n) = ", i break a, b, = b, a + b def main(): """Main program""" n = input("\nHow many numbers of the sequence would you like? ") find_fibonacci(n) if __name__ == '__main__': main()