Chen Primes: A Step Toward Understanding Prime Pairs
Chen primes are special primes connected to prime-pair research. The basic idea shows how this family relates to...
Circular Primes: When Digit Rotations Stay Prime
A circular prime is a prime number that stays prime after every rotation of its digits. The number...
Cousin Primes: Prime Pairs That Differ by 4
Cousin primes are prime pairs separated by 4. Examples, gap comparisons, and the open question of infinitely many...
Emirp Numbers: Primes That Reverse to Another Prime
An emirp is a non-palindromic prime whose reversed digits form a different prime. Examples and reversal checks distinguish...
Fermat Primes: Definition and Examples
Fermat primes have the form 2^(2ⁿ) + 1. Known examples, composite Fermat numbers, and geometric links explain why...
Palindromic Primes: Prime Numbers That Read Both Ways
A palindromic prime is a prime number whose digits read the same from left to right and right...
Pseudoprimes: Composite Numbers That Fool Prime Tests
A pseudoprime is a composite number that passes a prime test it was not supposed to pass. It...
Repunit Primes: Primes Made Only of Ones
Repunit primes contain only the digit 1 in a chosen base. Their form, examples, and rarity show why...
Safe Primes: Meaning and Examples
A safe prime has the form 2p + 1 where p is also prime. Examples, checks, and the...
Sophie Germain Primes: What They Are
A Sophie Germain prime is a prime p for which 2p + 1 is also prime. Examples, testing...
Truncatable Primes: Removing Digits Without Losing Primality
Truncatable primes remain prime as digits are removed from a side. Definitions, examples, and checks explain how this...
11 articles in Special Prime Numbers