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Math Help - Prime Numbers and Divisibility

  1. #1
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    Prime Numbers and Divisibility

    How do I go about proving this statement.

    Use the division theorem to show that every prime except 2 and 3 is of the form 6n+1 or 6n+5.

    The division theorem states:
    For integers a and b, with b>0, there exist unique integers q and r satisfying a=qb+r, 0≤r<b.
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  2. #2
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    Let p>3 be a prime.

    Use the division theorem with a=p and b=6. You obtain q and r such as stated in the theorem.
    Since p is odd, what can you say about r ?
    Finally, try to find a reason to eliminate the cases you don't want (A good way to show something isn't prime is to find a divisor different from 1 and the thing)
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