# Forbidden number in Fibonacci

Let $$F_n = F_{n-1}+ F_{n-2}$$ be the $$n^\text{th}$$ Fibonacci number $$(n>0)$$, where $$F_1=1$$ and $$F_2=1$$.

If we consider the last 3 digits of the Fibonacci numbers, not all numbers from 0 to 999 appear in the sequence.

$$\quad$$ 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 597, 584, 181, ...

What is the largest integer from 0 to 999 that doesn't appear in this sequence?

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