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ebaines Posts: 10,138, Reputation: 5589
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#6

Mar 15, 2012, 02:31 PM
I think what they wanted was for you try n = 1, n=10 , and n=41. If you do that you get:

For n=1: 1^2 - 1 + 41 = 41, which is a prime number
For n= 10: 10^2 - 10 + 41 = 131, which is a prime number
For n = 41: 41^2 - 41 + 41 = 41^2 = 1681, which is NOT prime

The stuff I added about n= 41+ a^2 is beyond the scope of the question - I just thought it was interesting to point out that there are many values for n that give a non-prime result, starting with n = 41.
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