1, 3, 4, 12, 20, 52, 92, 192, 322, 850, 1490, 3122, 5210, 13806, 23834, 50174, 82978, 220462, 382242, 800114, 1334742, 3530878, 6101600, 12843980, 21242476, 56440776, 97845358, 204811086, 341687150, 903923790, 1562078446, 3288017550, 5438140046, 14448668558