A047105 T(n,n-3), array T as in A047100.
1, 3, 5, 31, 120, 491, 2016, 8039, 31884, 126281, 498558, 1965077, 7740246, 30473582, 119948507, 472129697, 1858535320, 7317392228, 28816569762, 113512547183, 447270667394, 1762899256258, 6950527615283, 27412071431285
Offset: 3