Positive integer where n is the abbreviation of English "positive integer". In mathematics, a positive integer refers to an integer greater than 0, which usually includes 1, 2, 3, 4, etc. These numbers have the properties of non-negative numbers and natural numbers, and can be represented by the symbol +N or n.

Positive integer is an important concept in mathematics, which has many important properties and uses. For example, in number theory, positive integer is one of the basic elements of arithmetic and can be used for basic operations such as addition, subtraction, multiplication and division. Positive integers have many practical applications, such as counting, combinatorial mathematics, probability theory and other fields.

One of the basic properties of positive integers is that they can be arranged and combined according to certain laws. For example, positive integers can be arranged into a series in order of size, which is called positive integer series or natural number series. This series has infinite elements, and with the increase of numerical value, the number of elements in the series also increases.

Application of positive integer in mathematics;

1 and positive integers are the basis of counting. In our daily life, we often need to count, and positive integers are our counting tools. For example, when we need to count the number of something, we will count it with positive integers.

2. Positive integers are the basis of mathematical operations. In mathematics, basic operations such as addition, subtraction, multiplication and division are based on positive integers. For example, when we need to calculate the sum of two positive integers, we will use addition operation; We use division when we need to calculate a positive integer divided by another positive integer.

3. Positive integers are often used to indicate the order or size of things. For example, on the number axis, positive integers indicate the direction to the right and negative integers indicate the direction to the left. For another example, when comparing the sizes of two things, we usually use a positive integer to represent the larger thing.

4. Positive integers are also used to express some special concepts. For example, in mathematics, positive integers are used to represent equal units of time and distance. For example, when calculating time, we often use positive integer units such as hours, days and months; When calculating the distance, we also use positive integer units such as kilometers and miles.