80657

Properties

Appears in sequences

• Primes p such that (p-1) and the period length of 1/p are both squares.at n=28A076516
• Primes of the form 81*k^2 - 72*k + 17.at n=4A154276
• a(n) = 81*n^2 - 72*n + 17.at n=32A154277
• Primes of the form p^2 + 2*p + 2 where p is prime.at n=17A157467
• Primes from twin primes by taking the factorial of each digit and adding them up.at n=45A165934
• Honaker primes of the form k^2 + 1.at n=3A176790
• Primes p such that gcd(phi(p-1), sigma(p-1)) = 1 with phi = A000010, sigma = A000203.at n=32A270539
• Values of terms in A380837 which are not in A379066.at n=31A380838
• Prime numbersat n=7892