for which the equation,

**x^2 – y^2 – z^2 = n**, has exactly

**two**solutions is

**n=27**

since

**34^2 – 27^2 – 20^2 = 27**

and

**12^2 – 9^2 – 6^2 = 27**.

It turns out that

**n=1155**is the least value for which there are exactly

**ten**solutions.

How many values of n less than one million have exactly ten distinct solutions?

Source: Project Euler