[Credits - Deekonda Saikrishna]

y^2 - x^2 = 1296 (Pythagoras theorem)
max value of x comes when y - x in min
so y - x =2
y + x = 648
y= 375 , x = 373 z = 36
min value of x > 36
smallest pyth triplets 3, 4, 5
36 = 3 * 12
so other sides = 4 * 12, 5 * 12
max - min areas = (18 * ( 323 - 48) = 4950