A025576 a(n) = T(n,[ n/2 ]+1), where T is the array defined in A025564.

1, 4, 10, 22, 61, 120, 356, 665, 2058, 3732, 11892, 21153, 68860, 120835, 399828, 694590, 2328066, 4013088, 13591364, 23284424, 79538750, 135580865, 466489520, 791862354, 2741310614, 4637009300, 16137748980, 27215510265, 95152639095, 160053426720