Shifts left under reversion.

Terms

a(0) =1a(1) =1a(2) =-1a(3) =3a(4) =-13a(5) =69a(6) =-419a(7) =2809a(8) =-20353a(9) =157199a(10) =-1281993a(11) =10963825a(12) =-97828031a(13) =907177801a(14) =-8716049417a(15) =86553001779a(16) =-886573220093