Answer:
a) d = 3 b) a(n) = 3n – 13 c) a(27) = 68
Explanation:
solutions are (x, y) = (29,13) and (9349, 4181), which lead to (a, b) = (15,5) and (4895 ... corresponding to integer values of x give the quadruples. (x, y, z ... Since no number congruent to 3, modulo 4, can be written as the sum of two squares ... k is odd, the equation x2 - (k2 - 4)y2 = 4 has smallest solution in positive integers .