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## 'Always Perfect' printed from http://nrich.maths.org/

Have you tried some simple cases to see if there is a
pattern?

If you have a number "$x$" the next number is "$x +1$". How
could you write four consecutive numbers?

If you can express $x^4 + \ldots + 16$ as a perfect square, the
two factors will be of the form $(x^2 +\ldots + 4)$.