MathDB

2

Part of 2004 Iran Team Selection Test

Problems(1)

Pell equation

Source: Iran TST 2004

1/9/2009
Suppose that p p is a prime number. Prove that the equation x^2\minus{}py^2\equal{}\minus{}1 has a solution if and only if p≡1(mod4) p\equiv1\pmod 4.
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