math-prime-number.html
            
                
                    
                        
                        * created: 2025-10-21T22:28
                        
                         
                        * modified: 2025-10-22T16:27
                        
                        
                    
                
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                Prime numbers
                description
                These are numbers that are only divisible by $1$ and itself.
                
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            Prime Numbers
A number p \in \mathbb{N}^{+} is a prime number, if it has exactly two positive divisors (1 and p). These numbers are the building blocks of all \mathbb{N}, since every natural number n<1 can be written as the product of prime numbers.
10 is the product of 2 and 5.
A lot of asymmetric methods in cryptography are base around prime numbers.
\mathbb{P} is the set of all prime numbers.
All prime numbers, except 2, are odd numbers.
The prime factor p of n \in \mathbb{n} , n>1 is defined as p \in \mathbb{P}: p | n.
Fundamental Theorem of Arithmetic
The fundamental theorem of arithmetic asserts that every number n \in \mathbb{N}, n>1 can be written as the product one or more p \in \mathbb{P}.
Furthermore n can be deconstructed in it's prime factors in a process called prime factorization. Numbers that are no prime numbers are also referred to as composite numbers.
Definition: Every n \in \mathbb{N}, n>1 can be written as the product of one or more prime numbers, i.e. n = \prod_{i=1}^k p_i with p_{i} \in \mathbb{P}. Every prime factor is uniquely defined through this product up to the order of the factors.
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