help

Sorry, I got it backwards !! Thanks EP.

4   is ONE    ( counting up to 1024)   maybe the ONLY one?

all primes (except 2--but 3 is obviously not a perfect square) are odd. That means the perfect square must be even. And as EP has said 4 is one of them and I also don't know if there are any other options.

How many perfect squares are 1 more than a prime?  

Brute Force.  I tried all of them from 1² to 100² inclusive.  4 is the only one I found.  Actually, I didn't try all of them.  It isn't necessary to try numbers whose square ends in a 1, 5, 6, or 9. 

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