# Number theory

Number Theory Level 4

$\large 1! , 2!, 3!, \ldots , 2016!$

The product of all but one of the integers above results in a perfect square. Which number is it?

If the number can be expressed as $$x!$$, where $$x$$ is some integer, submit $$x$$ as your answer.

 Notation: $$!$$ denotes the factorial notation. For example, $$8! = 1\times2\times3\times\cdots\times8$$.

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