Exponential reversion of rooted trees A000081.

Terms

a(0) =1a(1) =-1a(2) =1a(3) =1a(4) =-14a(5) =64a(6) =-97a(7) =-1376a(8) =15915a(9) =-68820a(10) =-467868a(11) =11504693a(12) =-85105325a(13) =-490922106a(14) =21504158897a(15) =-242026388646a(16) =-848338391966