[ exp(14/19)*n! ].

Terms

a(0) =2a(1) =4a(2) =12a(3) =50a(4) =250a(5) =1504a(6) =10530a(7) =84241a(8) =758175a(9) =7581750a(10) =83399256a(11) =1000791076a(12) =13010283997a(13) =182143975962