A047007 T(n,n+2), array T given by A047000.
1, 3, 9, 30, 103, 366, 1323, 4859, 18033, 67531, 254620, 965592, 3679039, 14074126, 54023919, 207985518, 802774173, 3105514305, 12037590980, 46743091795, 181796906808, 708073498446, 2761428873186, 10782065189898, 42144216934185
Offset: 0