Followed by 48. According to the law, 22+6 is 28, 28+7 is 35, and 35+ 15 is 50, so it is followed by 48.

For this kind of searching rule, it is necessary to memorize the operational relationship of various numbers.

For example, squares and cubes of various numbers and their neighbors, so that when you see a number, you can feel it. This is the premise of understanding the theme of digital reasoning quickly and accurately. Common numerical relationships to remember are as follows:

(1) square relation: 2-4, 3-9, 4- 16, 5-25, 6-36, 7-49, 8-64, 9-8 1,10-64.

13- 169, 14- 196, 15-225, 16-256, 17-289, 18-324, 19-36 1,20-400

(2) Cubic relationships: 2-8, 3-27, 4-64, 5- 125, 6-2 16, 7-343, 8-5 12, 9-729,/kloc-.