A339493 a(n) = A333650(n, 3) for n >= 3; a(1) = a(2) = 0.
0, 0, 4, 11, 24, 52, 110, 228, 467, 949, 1916, 3848, 7696, 15342, 30505, 60527, 119892, 237156, 468590, 925032, 1824727, 3597289, 7088216, 13961168, 27489168, 54110618, 106489245, 209531251, 412217072, 810865812, 1594878078, 3136673996, 6168522827, 12130206941
Offset: 1