210708domain: NAppears in sequencesNumbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 34.at n=26A031712Total number of palindromic primes in base 4 below 4^n.at n=20A117777Total number of palindromic primes in base 4 below 4^n.at n=21A117777a(n) = 729*n^2 + 27.at n=17A158645