T(n,k)=Number of nXk 0..3 arrays with rows and columns in nondecreasing order.

Terms

a(0) =4a(1) =10a(2) =10a(3) =20a(4) =86a(5) =20a(6) =35a(7) =561a(8) =561a(9) =35a(10) =56a(11) =2861a(12) =14178a(13) =2861a(14) =56a(15) =84a(16) =12068a(17) =276427a(18) =276427a(19) =12068a(20) =84a(21) =120a(22) =43947a(23) =4249486a(24) =21907055a(25) =4249486a(26) =43947a(27) =120a(28) =165a(29) =142376