A055222 T(2n+6,n), array T as in A055216.
1, 8, 45, 211, 891, 3510, 13170, 47672, 167898, 578769, 1961103, 6552549, 21641343, 70784235, 229620285, 739640331, 2368022638, 7541358405, 23905443556, 75468582776, 237388273398, 744299007994, 2326899224352
Offset: 0