Column 2 of triangle A128320.

Terms

a(0) =1a(1) =5a(2) =12a(3) =73a(4) =418a(5) =3110a(6) =23920a(7) =207549a(8) =1885166a(9) =18417710a(10) =187881112a(11) =2018628090a(12) =22533601892a(13) =261966343388