330329

Properties

Appears in sequences

• Primes that remain prime through 4 iterations of function f(x) = 3x + 2.at n=15A023307
• Smaller of twin primes whose middle term is a multiple of A002110(5)=2310.at n=28A060231
• Smaller of twin primes whose mean (average) is a multiple of A002110(6)=30030.at n=3A060232
• Smaller of twin primes of the form P=j*P(i)#-1 and P=j*P(i)#+1 with 0 < j < P(i+1), where P(i) denotes i-th prime and P(i)# the i-th primorial number A002110(i).at n=17A087732
• Primes that are the concatenation of k and k-1 for some k, where the concatenation of k-2 and k-3 is also prime.at n=6A156120
• Sophie Germain primes that are also highly cototient numbers.at n=28A209194
• Numbers k such that phi(sigma(k))/k < phi(sigma(m))/m for all m < k, where sigma is the sum of divisors function (A000203) and phi is Euler's totient function (A000010).at n=35A293711
• Numbers k such that phi(psi(k))/k < phi(psi(m))/m for all m < k, where phi is Euler's totient function (A000010) and psi is the Dedekind psi function (A001615).at n=37A293713
• Numbers k where records occur for phi(k)/phi(k+1), where phi is the Euler totient function (A000010).at n=31A335070
• Prime numbersat n=28433