A027119 a(n) = A027113(n, 2n-1).
1, 4, 9, 23, 59, 154, 407, 1088, 2935, 7980, 21843, 60139, 166425, 462638, 1291245, 3616923, 10164335, 28648092, 80960915, 229360649, 651237509, 1852936294, 5282196109, 15084862158, 43150636493, 123624304356, 354689105733
Offset: 1