a(n) = floor( exp(11/16)*n! ).

Terms

a(0) =1a(1) =3a(2) =11a(3) =47a(4) =238a(5) =1431a(6) =10023a(7) =80185a(8) =721673a(9) =7216730a(10) =79384035a(11) =952608429a(12) =12383909588a(13) =173374734243