2116566392domain: NAppears in sequencesa(n) = 6*a(n-1)-8*a(n-2) for n > 10; a(0)=221, a(1)=1938, a(2)=8673, a(3)=73729, a(4)=589855, a(5)=7561526, a(6)=34593784, a(7)=218391421, a(8)=2116566392, a(9)=8522858480, a(10)=34225586144.at n=8A177422