A linear divisibility sequence of order 8.

Terms

a(0) =1a(1) =4a(2) =16a(3) =72a(4) =271a(5) =1024a(6) =3809a(7) =13968a(8) =50992a(9) =185364a(10) =672079a(11) =2433024a(12) =8798609a(13) =31797532a(14) =114864976a(15) =414821664a(16) =1497814207a(17) =5407599616a(18) =19521754897a(19) =70471314792a(20) =254385558128a(21) =918256161068