1 and mathematical thinking are very powerful. Can be used in different learning stages to help you solve the formula. At the same time, it also provides a collection of various formulas, automatic drawing of graphics and so on. Is a software that can arrange four-digit combinations.

2. The permutation and combination calculator is a simple and practical mathematical formula calculator. The software is convenient and simple. As long as the user enters a four-digit value, it can help the user to calculate all the results quickly.