A047037 T(n,n+2), array T as in A004730.
1, 3, 10, 35, 125, 455, 1680, 6270, 23591, 89335, 340076, 1300234, 4989504, 19206500, 74132230, 286802444, 1111864311, 4318284037, 16798674426, 65444081290, 255290775209, 997047334415, 3898217039280, 15256167628139
Offset: 0