31517

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 75.at n=24A020414
• Let p = prime(sigma(n)) and q = prime(phi(n)), then p is in the sequence if p-q = 6.at n=38A103176
• a(n) is the smallest prime divisor of the number obtained from concatenation of the first n primes.at n=54A104644
• Primes from merging of 5 successive digits in decimal expansion of the Euler-Mascheroni Constant.at n=24A104939
• Prime factors in a divisibility sequence of the Lucas sequence v(P=3,Q=5) of the second kind.at n=16A164816
• Primes of the form 3*k^2 + 9*k + 5.at n=36A171838
• Integers k such that 2^(k-1) == 1 (mod k) and 2^(m-1) == 1 (mod m), where m = k*(A000265(k-1) - 1) + 1 and A000265 gives the odd part of its argument.at n=20A187849
• Primes from merging of 5 successive digits in decimal expansion of Euler-Mascheroni constant.at n=26A198779
• Numbers k such that F(3*k)/(2*F(k)) is prime, where F(m) is the m-th Fibonacci number.at n=22A227576
• Primes having primitive roots 2, 3, 5, 7, 11, and 13.at n=27A241047
• Primes p such that (p^2+2)/3 and (p^4+2)/3 are prime.at n=27A256811
• Numbers k such that (9^k + 7^k)/16 is prime.at n=6A301369
• Prime numbersat n=3392