2156564411

Appears in sequences

• Lesser of twin primes p >= 5 for which phi(p+1)/phi(p-1) reaches record value, where phi(n) is the Euler totient function (A000010).at n=18A326356
• a(n) is the least prime of the form 2*x+1 where x is the product of n consecutive primes.at n=8A347866
• a(n) is the largest prime of the form P+1 where P divides prime(n)# and p# denotes the product of all primes <= p.at n=9A365021