i am having some trouble with this problem.(adsbygoogle = window.adsbygoogle || []).push({});

show that there are infinitely many integers n so that n^2+(n+1)^2 is a perfect square. (reduce to pell's equation).

i know pell's equation but don't know how to apply it with this problem.

pell's equation: n*x^2 + 1 = y^2.

-thanks.

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# Reducing to Pell's equation.

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