152847domain: NAppears in sequencesa(n) = 529*n^2 - 2*n.at n=16A158364Let p = prime(n). Smallest j such that q = j*2*p^3-1, r = j*p*2*q^2-1, s = j*p*2*r^2-1, and j*p*2*s^2-1 are prime numbers.at n=18A224612