What is the rarest prime?

The rarest prime number is considered to be the Ramanujan prime, named after the famous Indian mathematician Srinivasa Ramanujan. This prime is a specific type of prime number that is not only rare but also holds special properties that make it unique.

Ramanujan primes are defined as prime numbers that can be expressed in a specific form known as the Ramanujan sum. These primes are denoted as Rn, where n is the position of the prime in the sequence of Ramanujan primes.

There are only five known Ramanujan primes as of now, and they are:

  • R1 = 2
  • R2 = 11
  • R3 = 17
  • R4 = 29
  • R5 = 41

These primes have been studied extensively by mathematicians due to their special properties and rarity. The discovery of new Ramanujan primes is a challenging task, making them some of the rarest primes in mathematics.