Well, the problem statement is in the title:(adsbygoogle = window.adsbygoogle || []).push({});

Given that n is an integer, show that 3n^{2}- 1 can't be the square of an integer.

Currently, I don't have any idea at all where to start. Method is probably to assume opposite and show that this leads to a contradiction.

Any hint as to where to start would be very appreciated!

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# Homework Help: Prove that 3n^2 - 1 can't be a square of a integer n

**Physics Forums | Science Articles, Homework Help, Discussion**