A047114 T(n,n-2), array T as in A047110.
1, 3, 9, 24, 73, 164, 534, 3187, 11000, 39888, 174411, 665360, 2528518, 10223830, 39909056, 154727890, 612630675, 2404810575, 9405235895, 37053238445, 145729990271, 572330060383, 2253751873412, 8875044032506
Offset: 2