E.g.f. satisfies: A(x) = x*(tan(tan(A(x)))+1).

A133939

E.g.f. satisfies: A(x) = x*(tan(tan(A(x)))+1).

Terms

    a(0) =0a(1) =1a(2) =2a(3) =6a(4) =40a(5) =440a(6) =5952a(7) =97104a(8) =1888640a(9) =42480000a(10) =1082119680a(11) =30814080000a(12) =970187827200

External references