Number of aperiodic rooted trees on n nodes with locally distinct multiplicities.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =5a(6) =8a(7) =17a(8) =30a(9) =55a(10) =101a(11) =194a(12) =352a(13) =663a(14) =1227a(15) =2275a(16) =4225a(17) =7877a(18) =14600a(19) =27158a(20) =50414a(21) =93666a(22) =173972a(23) =323286a(24) =600353a(25) =1115407a(26) =2071843a(27) =3848794a(28) =7149196a(29) =13280874