Perplexing Polynomial Puzzle (Posted on 2005-06-13)
Ask an opponent to choose a polynomial p(x) with nonnegative integer coefficients (of any degree). Tell him you can determine what it is (degree and coefficients) with just two values: you choose a and ask for p(a), then choose b and ask for p(b). What is a winning strategy?
This is a really great problem. Too bad the rating scale only goes up to 5. Who was the dope who gave this a 4? You can change your rating by rerating a problem, by the way.