The third left hand column of triangle A167591.

Terms

a(0) =9a(1) =120a(2) =952a(3) =5664a(4) =27888a(5) =120064a(6) =467712a(7) =1686528a(8) =5719296a(9) =18450432a(10) =57108480a(11) =170713088a(12) =495366144a(13) =1401028608a(14) =3874881536a(15) =10508304384a(16) =28005433344a(17) =73485778944a(18) =190154539008a(19) =485895438336