## Prime Square Sums

#### Problem

The prime number 13 is called a Pythagorean prime because it can be written as the sum of two square numbers.

2^{2}+ 3^{2}= 4 + 9 = 13.

How many Pythagorean primes are there below 100?

Problem ID: 123 (Oct 2003) Difficulty: 2 Star