E.g.f.: exp(sin(arctan(x))).

Terms

a(0) =1a(1) =1a(2) =1a(3) =-2a(4) =-11a(5) =16a(6) =301a(7) =-104a(8) =-15287a(9) =-20096a(10) =1239481a(11) =4427776a(12) =-146243459a(13) =-954111872a(14) =23567903269a(15) =243390205696