c0 = 69^2 - 50^2 = 19 * 119 = 2261

c1 = 18^2 - 47^2 = -29 * 65 = -1885

c2 = 66^2 - 42^2 = 24 * 108 = 2592

c3 = 51^2 - 9^2 = 42 * 60 = 2520

c = 51^2 - 8^2 = 43 * 59 = 2537

>>7267490

It's good