T(n,n-1), array T as in A054098.

Terms

a(0) =1a(1) =3a(2) =3a(3) =11a(4) =33a(5) =145a(6) =747a(7) =4607a(8) =32873a(9) =266969a(10) =2431611a(11) =24554191a(12) =272289633a(13) =3289836257a(14) =43017800315a(15) =605289111695