The teacher and Xiaoming have an interesting conversation about the multiplication formula Sanqi and Xiaosan.

Lao Wang asked his son to recite the multiplication formula. When he recited it to a few minutes, the little guy couldn't remember it for a moment. Lao Wang said: Idiot, I can't remember this. Think about what it has to do with March 9. My son suddenly said loudly, I remember, Sanjiu Ganmao Ling, Sanjiu Weitai.

1 1 1 gets one, 122 gets two, 222 gets four, 133 gets three, 236 gets three, 339 gets seven, 2748, Women's Day on March 8th, May 1st, Children's Day on May 8th.

One by one, two by one, three by one, 3 14, 4 15, 5 16, 6 17, 7 18, 8199920.