256080domain: NAppears in sequencesNumbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 23.at n=21A031701a(n) = 529*n^2 + 2*n.at n=21A158367Values of the difference d for 7 primes in geometric-arithmetic progression with the minimal sequence {7*7^j + j*d}, j = 0 to 6.at n=22A209206