A027912 T(2n-1,n-2), T given by A027907.
1, 5, 28, 156, 880, 5005, 28665, 165104, 955434, 5550755, 32355917, 189147400, 1108476720, 6510243495, 38308997100, 225810489168, 1333057076890
Offset: 2
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