228479

Properties

Appears in sequences

• a(n) = least primitive factor of 2^(2n+1) - 1.at n=35A002184
• Smallest prime factor of Mersenne numbers 2^p-1, where p is prime.at n=19A016047
• Smallest prime factor of composite Mersenne numbers: lpf(2^p-1) where 2^p-1 is composite and p is prime.at n=10A136030
• Prime factors of 2^A054723(n)-1, ordered by increasing n, then by increasing size of the factors.at n=24A244453
• Primes of the form p^4+q^4+r^4-4 with p<=q<=r all prime.at n=29A256380
• a(n) is the least prime factor (> 3) in the factorization of 2^(2*prime(n))-1.at n=19A363673
• Prime numbersat n=20301