1, arithmetic progression, the difference between the former number and the latter number is equal. For example: 1, 3, 5, 7, 9, …
Inverse arithmetic series, the difference between the last number and the previous number is equal. For example: 10, 8, 6, 4, 2 …;
2. Parageometric series, that is, the quotient of the previous number divided by the latter number is equal. For example: 2, 4, 8, 16, 32 …;
Inverse geometric series means that the quotient of the last number divided by the previous number is equal. For example:1024,512,256, 128, …
3. Rabbit series, that is, numbers with odd numbers and numbers with even numbers form laws respectively.
For example, 8, 15, 10, 13, 12,1,(14), (9) Here 8,/kloc-
4. Prime number sequence laws, such as: 2, 3, 5, 7, 1 1, (13), (17) ... These mathematics are prime numbers;
Note: there is only one general exam, and junior high school exams are easy to appear, so pay special attention.
5. "Square series" and "cubic series".
For example: square series: 1, 4, 9, 16, 27, 64, 125, …
Cubic series: 1, 8, 27, 64, 8 1, 256, 625, …
6. The difference between adjacent numbers is regular.
The difference between numbers presents arithmetic progression, for example: 1, 3,7,13,21,3 1, 43, …
The difference between numbers presents geometric series, such as: 1, 3,7,15,31,63, …
7. There are rules to follow between multiple numbers (this question is rarely examined)
Peibonach series, that is, the sum of any two consecutive numbers is equal to the third number,
For example: 1, 1, 2,3,5,8,13,21,34, …
The sum of any three consecutive numbers is equal to the fourth number,
For example: 1, 1, 1, 3, 5, 9, 17, 3 1, 57, 105, …