Fourth left hand column of triangle A163940.

Terms

a(0) =0a(1) =4a(2) =49a(3) =246a(4) =834a(5) =2250a(6) =5214a(7) =10829a(8) =20696a(9) =37044a(10) =62875a(11) =102124a(12) =159834a(13) =242346a(14) =357504a(15) =514875a(16) =725984a(17) =1004564a(18) =1366821a(19) =1831714a(20) =2421250a(21) =3160794a(22) =4079394a(23) =5210121a(24) =6590424a(25) =8262500a(26) =10273679a(27) =12676824a(28) =15530746a(29) =18900634