Simply find the regular topic () () 3 () 5 6 7. As can be seen from 5.6.7 in the second half, it is arranged in normal numerical order. (1 )(2) 3 (4) 5 eggplant four seasons 6 7.

2.

Find the law of simple and even numbers 1357 () () 2468 () () Solution 1, simple and even numbers. Solution 2: The difference between two adjacent numbers is 2.3-1= 2; 5-3 =2 Option 3: Let the children write their own numbers in normal order. Then mark the numbers appearing in the topic below the numbers, so that children can see the arrangement rules of the numbers in the topic at a glance (as shown below)1357 (9) (11) (13) 2468 (.

3.

Interval 2 to 3: 1 Looking for rules and regulations. (1)147 () (2) 369 () 2. (1)159 () (2) 2665438 7-4 = 3 hooks (2) 6-3 = nine