short answer: no.
slightly longer answer: x^2+1 has a solution in Z2. find it.
Hello, Duke!
We have: .
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We find that: .
Therefore, has no solutions.
We have: .
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. . . . . . . . . . .
We find that: .
Therefore, has one solution:
We have: .
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has solutions if for a positive integer
Are there any other solutions?
. . I don't know.