1687623domain: NAppears in sequencesa(n) = 6*a(n-1)-8*a(n-2)-3 for n > 10; a(0)=753, a(1)=5043, a(2)=25779, a(3)=213003, a(4)=1687623, a(5)=18171219, a(6)=73344977, a(7)=769993485, a(8)=4480470831, a(9)=17582325855, a(10)=69524390079.at n=4A177423