281683

Properties

Appears in sequences

• Prime divisors of solutions to 10^n == 1 (mod n).at n=18A066364
• Prime numbers P such that Q=2*P^2-1, R=2*Q^2-1, S=2*R^2-1 and T=2*S^2-1 are all prime numbers.at n=0A245659
• a(n) = a(n-3) + a(n-2) + gcd(a(n-2), a(n-1)) with a(1) = a(2) = a(3) = 1.at n=42A370202
• Prime numbersat n=24575