Problem 104

Pandigital Fibonacci ends

The Fibonacci sequence is defined by the recurrence relation:

F_{n}= F_{n1}+ F_{n2}, where F_{1}= 1 and F_{2}= 1.

It turns out that F_{541}, which contains 113 digits, is the
first Fibonacci number for which the last nine digits are 1-9 pandigital
(contain all the digits 1 to 9, but not necessarily in order). And F_{2749}, which contains 575 digits, is the first Fibonacci number for which the first nine digits are 1-9 pandigital.

Given that F_{k} is the first Fibonacci number for which the first nine digits AND the last nine digits are 1-9 pandigital, find *k*.

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These problems are part of
Project Euler
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