67421

Properties

Appears in sequences

• Numbers k such that 7*2^k - 1 is prime.at n=14A001771
• Numbers k such that (14^k - 1)/13 is prime.at n=8A006032
• Primes p such that sum of squares of even-position digits equals the sum of squares of odd-position digits of p.at n=25A076168
• Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d = 2, 4 or 6) and forming d-pattern=[6,2,4]; short d-string notation of pattern = [624].at n=15A078853
• Primes such that the sum of any two terms, plus one, is a prime.at n=6A133761
• Primes p such that the left prime neighbors p1, p2 of p as well as the right prime neighbors q1, q2 of p form twin prime pairs and the sum p1 + p2 + p + q1 + q2 is also prime.at n=33A138396
• Primes of the form 6n^2 + 5.at n=33A201600
• Numbers k such that (11^k - 2^k)/9 is prime.at n=11A210506
• Primes that are values of A215240.at n=19A320041
• Number of nonnegative solutions to (x_1)^2 + (x_2)^2 + ... + (x_9)^2 <= n.at n=23A341404
• Prime numbersat n=6715