Table related to labeled rooted trees, cycles and binary trees.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =3a(6) =6a(7) =18a(8) =25a(9) =15a(10) =24a(11) =96a(12) =190a(13) =210a(14) =105a(15) =120a(16) =600a(17) =1526a(18) =2380a(19) =2205a(20) =945a(21) =720a(22) =4320a(23) =13356a(24) =26488a(25) =34650a(26) =27720a(27) =10395a(28) =5040a(29) =35280