T(n,n+1), array T as in A047089.

Terms

a(0) =1a(1) =2a(2) =7a(3) =22a(4) =79a(5) =278a(6) =1021a(7) =3752a(8) =14023a(9) =52640a(10) =199248a(11) =757360a(12) =2892977a(13) =11088266a(14) =42640759a(15) =164413606a(16) =635490703a(17) =2461411460a(18) =9551605730a(19) =37126976390a(20) =144528973888a(21) =563386487780