528510

Appears in sequences

• Numbers k such that 2*k-1, 4*k-1, 6*k-1, 8*k-1 and 10*k-1 are primes.at n=25A124488
• Numbers n such that usigma(n) = usigma(2*n+1) where usigma(n) = A034448(n).at n=22A286837