137439477761domain: NAppears in sequencesa(n) = 2 * (4^n + 2^n) + 1.at n=18A085601Numbers that are both Poulet and Proth.at n=18A242880a(0)=2; for n > 0, a(n) = 2^(2*n-1) + 2^n + 1.at n=19A343175