[ exp(3/11)*n! ].

Terms

a(0) =1a(1) =2a(2) =7a(3) =31a(4) =157a(5) =945a(6) =6620a(7) =52962a(8) =476658a(9) =4766581a(10) =52432391a(11) =629188699a(12) =8179453089a(13) =114512343252