Euler program (python) Problem 25

1000-digit Fibonacci Numberproblem 25

The Fibonacci sequence is defined by the recurrence relation:

f n = f n? 1 + f n? 2, where F1 = 1 and F2 = 1.

Hence The first terms would 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, are the first term to contain three digits.

What's the index of the first term in the Fibonacci sequence to contain? digits?

Go to the "thread for Problem" in the forum.

Python code:

A,b=0,1count=1while B//pow (10,999) <1:    count+=1    a,b=b,a+bprint (count)

Time : <1s

Euler program (python) Problem 25