[ exp(10/23)*n! ].

Terms

a(0) =1a(1) =3a(2) =9a(3) =37a(4) =185a(5) =1112a(6) =7784a(7) =62279a(8) =560514a(9) =5605143a(10) =61656576a(11) =739878916a(12) =9618425913a(13) =134657962794