A026578 T(2n-1,n-2), T given by A026568.
1, 3, 13, 60, 225, 1148, 4235, 22296, 82425, 440308, 1634435, 8809736, 32819839, 178029138, 665162897, 3625521728, 13577768505
Offset: 2
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