T(2n+1,n), array T as in A054126.

Terms

a(0) =3a(1) =13a(2) =68a(3) =394a(4) =2396a(5) =14925a(6) =94248a(7) =600498a(8) =3851012a(9) =24821845a(10) =160646528a(11) =1043245180a(12) =6794418992a(13) =44360061964a(14) =290244849376