[ exp(8/11)*n! ].

Terms

a(0) =2a(1) =4a(2) =12a(3) =49a(4) =248a(5) =1489a(6) =10429a(7) =83439a(8) =750954a(9) =7509543a(10) =82604983a(11) =991259805a(12) =12886377471a(13) =180409284603