[ exp(9/17)*n! ].

Terms

a(0) =1a(1) =3a(2) =10a(3) =40a(4) =203a(5) =1222a(6) =8557a(7) =68460a(8) =616146a(9) =6161460a(10) =67776061a(11) =813312734a(12) =10573065543a(13) =148022917610