Triangle read by rows: T(n,k) = (4*n - 3*k)!/((n-k)!^4*k!).

Terms

a(0) =1a(1) =24a(2) =1a(3) =2520a(4) =120a(5) =1a(6) =369600a(7) =22680a(8) =360a(9) =1a(10) =63063000a(11) =4804800a(12) =113400a(13) =840a(14) =1a(15) =11732745024a(16) =1072071000a(17) =33633600a(18) =415800a(19) =1680a(20) =1a(22) =246387645504a(23) =9648639000a(24) =168168000a(25) =1247400a(26) =3024a(27) =1a(31) =61108047000a(32) =672672000a(33) =3243240