The Fibonacci Sequence is defined by the recurrence relation:
Fn = Fn-1 + Fn-2, 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 and F12 = 144
The 12th term, F12, is the first term to contain three digits. Find the index of the first term in the Fibonacci sequence to contain n digits. Begin by entering the number of digits.