The second time, two people informed two people and met four people.

3->； eight

4->； 16

Finally notify the remaining 10 people.

The origin of mathematical wide angle;

"Mathematics Wide Angle" is a newly added unit in the experimental textbook of compulsory education curriculum standards since the first volume of the second grade, and it is a new attempt made by the new textbook in infiltrating mathematical thinking methods into students.

The textbook is based on students' familiar and interesting life scenes, and pays attention to infiltrating these mathematical thinking methods into students, putting learning activities in simulated scenes, providing students with opportunities for operation and activities, initially cultivating students' awareness of orderly and comprehensive thinking, and laying the foundation for students to learn combinatorial mathematics and probability statistics in the future.