a(n) = floor(exp(14/23) * n!).

Terms

a(0) =1a(1) =1a(2) =3a(3) =11a(4) =44a(5) =220a(6) =1323a(7) =9263a(8) =74109a(9) =666985a(10) =6669851a(11) =73368371a(12) =880420460a(13) =11445465992a(14) =160236523888