426389

Properties

Appears in sequences

• Markoff (or Markov) numbers: union of positive integers x, y, z satisfying x^2 + y^2 + z^2 = 3*x*y*z.at n=35A002559
• Primes of the form F(i)^2 + F(j)^2, where F() are Fibonacci numbers.at n=16A045703
• Define C(n) by the recursion C(0) = 1 + I where I^2 = -1, C(n+1) = 1/(1+C(n)); then a(n) = (-1)^n/Im(C(n)) where Im(z) is the imaginary part of the complex number z.at n=13A069921
• Non-Fibonacci Markoff numbers.at n=21A111032
• Markov numbers that are prime.at n=15A178444
• Primes of the form 3n^2 + 2.at n=40A257163
• Primes whose base-8 representation is a perfect square in base 10.at n=31A267490
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 0, a(1) = 2, a(2) = 0, a(3) = 1.at n=29A295682
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 2, a(1) = 2, a(2) = 1, a(3) = 1.at n=28A295690
• a(n) = (x(n)^2 + 1)/m(n), with m(n) = A002559(n) (Markoff numbers) and x(n)= A324601(n), for n >= 3. The Markoff uniqueness conjecture is assumed to be true.at n=45A309161
• Positive integers k such that (k+1)^4 has a divisor congruent to -1 modulo k.at n=58A350916
• a(0) = 2, a(1) = 5, and a(n) = 7*a(n-1) - a(n-2) - 4 for n >= 2.at n=7A350922
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 2, a(2) = 5, a(3) = 7.at n=26A362388
• Markoff numbers that are powers of one odd prime or twice powers of one odd prime.at n=19A386894
• The odd Markoff numbers.at n=26A388291
• Prime numbersat n=35878