| 次方 | to the power of |
| -------- | --------------------------- |
| 几分之几 | n over n |
| 阶乘 | factorial of |
| 等差数列 | arithmetic series |
| 等比数列 | geometric series |
| 排列组合 | Permutation and Combination |
| 根号 | square root of |
| 几次根 | nth root of |
| 因式分解 | factorize |
Permutation排列: 16选3=16x15x14
Combination组合:16选3=16C3=16!/13!*3!