T(n,n), array T as in A047140.

Terms

a(0) =1a(1) =2a(2) =4a(3) =10a(4) =38a(5) =142a(6) =470a(7) =1576a(8) =5940a(9) =22714a(10) =83456a(11) =305088a(12) =1158606a(13) =4456076a(14) =16946498a(15) =64189932a(16) =246350606a(17) =952607962a(18) =3675557676a(19) =14158562010a(20) =54805236890a(21) =213011072542a(22) =828185178452