6700417

Properties

Appears in sequences

• Largest prime factor of 2^n + 1.at n=32A002587
• Largest prime factor of 16^n + 1.at n=8A002590
• a(n) = largest prime factor of n^n - 1.at n=14A006486
• Prime factors of Fermat numbers.at n=11A023394
• Triangle in which n-th row gives prime factors of n-th Fermat number 2^(2^n)+1.at n=6A050922
• Duplicate of A050922.at n=6A067387
• Largest prime factor of the n-th Fermat number F(n) = 2^(2^n) + 1.at n=5A070592
• A006530(x)=2 is a local minimum if x=2^n. Running upward with argument x, the largest prime divisor should increase. The value of first peak is a(n).at n=32A102643
• Anti-elite primes: a prime number p is called anti-elite if only a finite number of Fermat numbers 2^(2^n)+1 are quadratic non-residues mod p.at n=34A128852
• Numbers k (between 2^(m-1) and 2^m) such that 2^(k-1) == 1 (mod k) and 2^(k-1-m) == k - 2^p (mod k) for some p > 0 with 2^p < k.at n=32A167612
• Prime factors of 2^128 - 1.at n=7A176689
• Primes p such that (p-1)/ord(2,p) > (q-1)/ord(2,q) for odd primes q < p.at n=23A226216
• Greatest prime factor of n^8+1.at n=15A240551
• Largest prime factor of 4^n + 1.at n=16A274903
• Largest prime factor of 4^n - 1.at n=31A274906
• Divisors of Fermat numbers.at n=12A307843
• Primes congruent to 1 (mod 3) that divide some Fermat number.at n=2A351332
• Numbers k that divide 2^(2^k) - 2^k + 1.at n=19A373580
• Prime numbersat n=457523