[ exp(15/17)*n! ].

Terms

a(0) =2a(1) =4a(2) =14a(3) =57a(4) =289a(5) =1739a(6) =12179a(7) =97436a(8) =876928a(9) =8769282a(10) =96462104a(11) =1157545250a(12) =15048088262a(13) =210673235669