T(n,n+2), array T given by A047010.

Terms

a(0) =1a(1) =3a(2) =10a(3) =34a(4) =120a(5) =434a(6) =1593a(7) =5916a(8) =22173a(9) =83695a(10) =317739a(11) =1212014a(12) =4641637a(13) =17836092a(14) =68736489a(15) =265562956a(16) =1028262867a(17) =3989193141a(18) =15503022891a(19) =60341894022a(20) =235193502470a(21) =917862682778