Chia hết cho 3
(3 3 số)
03,06,09,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60,63,66,69,72,75,78,81,84,87,90,93,96,99
Chia 3 dư 1
(3 4 số)
00,01,04,07,10,13,16,19,22,25,28,31,34,37,40,43,46,49,52,55,58,61,64,67,70,73,76,79,82,85,88,91,94,97
Chia 3 dư 2
(3 3 số)...