a(n) = composite(n)*2^(n - 3).

Terms

a(0) =1a(1) =3a(2) =8a(3) =18a(4) =40a(5) =96a(6) =224a(7) =480a(8) =1024a(9) =2304a(10) =5120a(11) =10752a(12) =22528a(13) =49152a(14) =102400a(15) =212992a(16) =442368a(17) =917504a(18) =1966080a(19) =4194304a(20) =8650752a(21) =17825792a(22) =36700160a(23) =75497472a(24) =159383552a(25) =327155712a(26) =671088640a(27) =1409286144a(28) =2952790016a(29) =6039797760