# Pi 123: A Curious Number with Many Applications

Pi is a mathematical constant that represents the ratio of a circle’s circumference to its diameter. It is approximately equal to 3.14159, but it has an infinite number of digits that never repeat or end. Pi is one of the most important and fascinating numbers in mathematics, as it appears in many formulas and equations that describe various phenomena in nature, science, and engineering.

However, pi is not the only number that has an infinite number of digits. There are many other numbers that are irrational, meaning that they cannot be expressed as a fraction of two integers. Some examples of irrational numbers are the square root of 2, the golden ratio, and Euler’s number.

One way to create new irrational numbers is to concatenate existing ones. For example, if we take the first three digits of pi (3.14) and append them to the first three digits of the square root of 2 (1.41), we get a new number: 3.14141. This number is also irrational, as it has an infinite number of digits that are not periodic or predictable.

One interesting question is: what happens if we concatenate pi with itself? That is, what if we take the first n digits of pi and append them to the next n digits of pi, and so on? For example, if n = 3, we get:

3.14159 26535 89793 23846 …

This number is called pi 123, as it is formed by taking one, two, and three digits of pi at a time. Pi 123 is also an irrational number, as it has an infinite number of digits that are not periodic or predictable.

## Properties of Pi 123

Pi 123 has some interesting properties that make it different from other irrational numbers. Some of these properties are:

- Pi 123 contains all the digits of pi in order, but not all the digits of pi appear in pi 123. For example, the digit 0 does not appear in pi 123 until the 32nd position, while it appears in pi at the 32nd position.
- Pi 123 contains infinitely many copies of pi as subsequences, but not all subsequences of pi appear in pi 123. For example, the subsequence 314159 does not appear in pi 123 until the 176th position, while it appears in pi at the first position.
- Pi 123 has a lower density of prime numbers than pi. A prime number is a positive integer that has exactly two factors: itself and one. The density of prime numbers in a sequence is the proportion of prime numbers in that sequence. For example, the density of prime numbers in the sequence 1, 2, 3, 4, 5 is 0.6, as three out of five numbers are prime. The density of prime numbers in pi is approximately 0.43 while the density of prime numbers in pi 123 is approximately 0.38.

## Applications of Pi 123

Pi 123 may seem like a trivial or arbitrary number, but it has some potential applications in various fields. Some of these applications are:

- Cryptography: Cryptography is the science of securing information by using codes and ciphers. One way to encrypt information is to use a key that is derived from an irrational number, such as pi or pi 123. The key can be used to transform the information into a secret message that can only be decrypted by someone who knows the key.
- Art: Art is the expression of human creativity and imagination through various forms and media. One way to create art is to use irrational numbers as sources of inspiration or patterns. For example, some artists have used pi or pi 123 to generate music, images, or sculptures.
- Education: Education is the process of acquiring knowledge and skills through instruction and experience. One way to teach mathematics is to use irrational numbers as examples or exercises. For example, some teachers have used pi or pi 123 to illustrate concepts such as fractions, decimals, or geometry.

## Conclusion

Pi 123 is a curious number that is formed by concatenating pi with itself. It is an irrational number that has an infinite number of digits that are not periodic or predictable. It has some interesting properties that make it different from other irrational numbers, such as containing all the digits of pi in order but not all the digits of pi appear in it; containing infinitely many copies of pi as subsequences but not all subsequences of pi appear in it; and having a lower density of prime numbers than pi.

Pi 123 also has some potential applications in various fields such as cryptography, art, and education. It can be used as a key to encrypt information, as a source of inspiration or patterns to create art, or as an example or exercise to teach mathematics. Pi 123 is a fascinating number that shows the beauty and diversity of mathematics.