Sum of Squares and Prime - Interesting Number Pattern ---> 14

Look at this

4 ^ 2 + 1 ^ 2 = 17 ---> Prime
9 ^ 2 + 4 ^ 2 = 97 ---> Prime
16 ^ 2 + 9 ^ 2 = 337 ---> Prime
25 ^ 2 + 16 ^ 2 = 881 ----> Prime
(The pattern breaks here) 36 ^ 2 + 25 ^ 2 = 1921 ----> Not a Prime but it is = 17 * 113 which are both primes :)