23099

Properties

Appears in sequences

• Primes of form k^2 - 5.at n=29A028877
• Decimal part of n^(1/11) starts with a 'nine digits' anagram.at n=10A034286
• Table read by rows where i-th row consists of primes P of the form P=j*P(i)# -1 or P=j*P(i)# +1 with 0 < j < P(i+1). Here P(r)# = A002110.at n=40A087715
• Primes of the form 4*k-1 such that 8*k-1 and 16*k-1 are also primes.at n=35A101791
• Highly cototient numbers that are prime, or intersection of A000040 and A100827.at n=38A105440
• The 2^n-th irregular prime.at n=10A105460
• Primes p such that 2p+1, 4p+3, 6p+5 are all primes.at n=23A107020
• Primes of the form prime(k)^2 + 2*prime(k-1) where prime(k) is the k-th prime number.at n=12A155820
• Supersafe primes.at n=38A181841
• Cyclops Sophie-Germain primes.at n=12A183058
• Safe primes that are also highly cototient numbers.at n=9A209193
• Sophie Germain primes that are also highly cototient numbers.at n=17A209194
• Indices of primes in the tribonacci-like sequence A214826.at n=10A242315
• Numbers x such that sigma(x)=sigma(V(x)), where sigma(x) is the sum of the divisors of x and V(x) the transform defined in A245252.at n=9A245469
• Primes congruent to 11 mod 111.at n=38A252893
• Smallest of five consecutive primes in arithmetic progression with common difference 90 and equal digit sums.at n=19A253232
• Primes of the form A060735(k) +- 1, where A060735 lists multiples of primorials (A002110) less than the next larger primorial.at n=39A257658
• Sophie Germain primes p such that p + 2 and p - 2 are semiprimes.at n=43A277993
• 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=27A293711
• 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=29A293713