Permutations. Shen A.

In life, “permutations” call a variety of things. This book contains initial information about what mathematicians are called a "group of rearrangements of the final set." We will show how to divide the permutations into “one” and “odd” and how it helps to analyze the well -known puzzle with 15 chips in the square of 4x4, how the rearrangement decomposes into cycles and why it is useful, why is the repetition of the same action with “cube Rubika ”sooner or later it will return it to its original position, and we will analyze the tasks, when solving which the permutation is useful. Typically, these issues are attributed to the “Higher Algebra” courses for junior students, but they are quite elementary, and we do not use any information beyond the limits of the middle classes of the school. (Although, of course, the habit of simple mathematical reasoning will come in handy.)