208391

Properties

Appears in sequences

• Primes p such that phi(p+1) = phi(p-1).at n=11A067890
• Primes of the form p^2 - p - 1, where p is prime.at n=30A091568
• Lesser of twin primes p for which phi(p-1) = phi(p+1), where phi(n) is the Euler totient function (A000010).at n=4A303549
• Prime numbersat n=18669