Number of labeled servers of dimension 3.

Terms

a(0) =1a(1) =3a(2) =12a(3) =56a(4) =294a(5) =1698a(6) =10624a(7) =71256a(8) =508188a(9) =3829652a(10) =30340464a(11) =251647872a(12) =2177440648a(13) =19596586584a(14) =182967013056