mod 6

Don Reble djr at
Sat Mar 22 22:34:58 CET 2003

>> If N is an integer, then neither N^2-N+1 nor N^2+N+1 is divisible by
>> any positive number of the form 6k+5.

>    I think that the proof is not comprete for A056650.
>    The following theorem should be proved.
>    T.3^n   p^2+p+1=3^n , p is prime, has no solution.

	Well, n^2-n+1 and n^2+n+1 are never divisible by 9.
	That should do it.
Don Reble       djr at

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