x^2=(5 17+30y^2)/(3y^2+ 1)= 10+507/(3y^2+ 1)

507=3* 13* 13

3y^2+ 1= 1,3， 13，39

3y^2=0

y^2=0，2/3，4，28/3，56，506/3

Y=0 or 2

X 2 = 517, 49 years old ->x=7.

So the positive integer solution only has x = 7 and y = 2.

According to symmetry, * * * has four groups of solutions: (7,2), (7,2), (-7.2), (-7,2).