a(n) = a(floor(n/2))*a(ceiling(n/2)), where a(0) = 1, a(1) = 2, a(2) = 3.

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =9a(5) =18a(6) =36a(7) =54a(8) =81a(9) =162a(10) =324a(11) =648a(12) =1296a(13) =1944a(14) =2916a(15) =4374a(16) =6561a(17) =13122a(18) =26244a(19) =52488a(20) =104976a(21) =209952a(22) =419904a(23) =839808a(24) =1679616a(25) =2519424a(26) =3779136a(27) =5668704a(28) =8503056a(29) =12754584