Fourth column (m=3) of triangle A090447.

Terms

a(0) =9a(1) =96a(2) =500a(3) =1800a(4) =5145a(5) =12544a(6) =27216a(7) =54000a(8) =99825a(9) =174240a(10) =290004a(11) =463736a(12) =716625a(13) =1075200a(14) =1572160a(15) =2247264a(16) =3148281a(17) =4332000a(18) =5865300a(19) =7826280a(20) =10305449a(21) =13406976a(22) =17250000a(23) =21970000a(24) =27720225a(25) =34673184a(26) =43022196a(27) =52983000a(28) =64795425a(29) =78725120