E.g.f.: exp(1 / (1 - arcsin(x)) - 1).

Terms

a(0) =1a(1) =1a(2) =3a(3) =14a(4) =85a(5) =640a(6) =5703a(7) =58760a(8) =685353a(9) =8925632a(10) =128231627a(11) =2014061568a(12) =34312150525a(13) =630043097216