Number of rooted twice-partitions of n where the composite rooted partition is strict.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =8a(6) =12a(7) =18a(8) =29a(9) =42a(10) =61a(11) =86a(12) =127a(13) =181a(14) =257a(15) =352a(16) =489a(17) =668a(18) =935a(19) =1270a(20) =1730a(21) =2312a(22) =3101a(23) =4112a(24) =5533a(25) =7345a(26) =9742a(27) =12785a(28) =16793a(29) =21821