Number of forests of identical trees.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =4a(5) =4a(6) =9a(7) =12a(8) =27a(9) =49a(10) =111a(11) =236a(12) =562a(13) =1302a(14) =3172a(15) =7746a(16) =19347a(17) =48630a(18) =123923a(19) =317956a(20) =823178a(21) =2144518a(22) =5623993a(23) =14828075a(24) =39300482a(25) =104636894a(26) =279794753a(27) =751065509a(28) =2023446206a(29) =5469566586