Find a number k such that n^4 + k is composite for all integer n.
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Anonymous2008-02-28 10:25
Well for starters, if n^4 + k is not even, then there is a chance that it might be a prime.
Clearly, we have to prove that n^4 + k is *not* prime.
That is rather easy to achieve, since n^4 is always even.
Therefore, n^4 + k where k is even shall do.
14 is even