Stable k-tree numbers.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =15a(6) =64a(7) =342a(8) =2344a(9) =19137a(10) =181204a(11) =1927017a(12) =22652805a(13) =290392448a(14) =4022276630a(15) =59749492128a(16) =946174967813