42521761

Properties

Appears in sequences

• Largest prime factor of 9^n + 1.at n=10A002592
• Cyclotomic polynomials at x=9.at n=20A019327
• Cyclotomic polynomials at x=-9.at n=20A020508
• a(n) = n^8 - n^6 + n^4 - n^2 + 1.at n=9A060892
• Largest prime factor of 9^(2n)+1 (A063270).at n=5A063271
• Largest prime factor of 9^(2n)+1 (A063270).at n=15A063271
• Largest prime factor of 3^n + 1.at n=20A074476
• Numbers of the form (3^s+1)/(3^r+1) for s > 1, 1 <= r <= s-1.at n=18A079672
• a(n) is the least prime such that the multiplicative order of 3 mod a(n) equals n, or a(n)=1 if no such prime exists.at n=39A143663
• Primes of the form Phi_k(3), the k-th cyclotomic polynomial evaluated at 3.at n=14A211874
• Primes of the form Phi(phi(k),3), the phi(k)-th Cyclotomic polynomial evaluated at 3, where phi is the Euler totient function.at n=6A211875
• Greatest prime factor of n^10+1.at n=8A240553
• Primes of the form n^4 - n^3 + n^2 - n + 1.at n=21A259257
• Largest prime factor of 9^n - 1.at n=19A274909
• Primes of the form Phi(k, -9), where Phi is the cyclotomic polynomial.at n=4A291991
• Primes of the form Phi(k, -3), where Phi is the cyclotomic polynomial.at n=14A292004
• Primes of the form Phi(k, 3), where Phi is the cyclotomic polynomial.at n=15A292007
• Primes of the form Phi(k, 9), where Phi is the cyclotomic polynomial.at n=3A292013
• a(n) = sigma_8(n^2)/sigma_4(n^2).at n=8A372966
• Smallest primitive prime factor of 9^n-1.at n=19A379642