[ exp(16/17)*n! ].

Terms

a(0) =2a(1) =5a(2) =15a(3) =61a(4) =307a(5) =1845a(6) =12917a(7) =103339a(8) =930059a(9) =9300596a(10) =102306556a(11) =1227678673a(12) =15959822761a(13) =223437518655