[ exp(7/15)*n! ].

Terms

a(0) =1a(1) =3a(2) =9a(3) =38a(4) =191a(5) =1148a(6) =8037a(7) =64297a(8) =578673a(9) =5786737a(10) =63654113a(11) =763849365a(12) =9930041753a(13) =139020584550