Daca (a, b)=21 ⇒ a=21x. b=21y
21x+21y=231⇒ 21(x+y)=231⇒ x+y=231:21=11
(x,y) apartine { (0,11), (1,10), (2,9), (3,8), (4,7), (5,6), (6,5), (7,4), (8,3), (9,2), (10,1), (11,0)}
Rezulta (a,b) apartine { (0,231), (21,210), (42,189), (63,168), (84,147), (105,126), (126,105), (147,84), (168,63), (189,42), (210,21), (231,0)}
