| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 16 |
| 5 | 27 |
| 6 | 79 |
| 7 | 126 |
| 8 | 331 |
| 9 | 632 |
| 10 | 1436 |
| 11 | 2509 |
| 12 | 6800 |
| 13 | 11218 |
| 14 | 26044 |
| 15 | 51958 |
| 16 | 114941 |
| 17 | 205183 |
| 18 | 502228 |
| 19 | 875545 |
| 20 | 2027193 |
| 21 | 3963938 |
| 22 | 8389190 |
| 23 | 15504996 |
| 24 | 37555290 |
| 25 | 66502859 |
| 26 | 145809046 |
| 27 | 292860564 |
| 28 | 621638120 |
| 29 | 1156065731 |
| 30 | 2701045579 |
[1,1,3,6,16,27,79,126,331,632,1436,2509,6800, 11218,26044,51958,114941,205183,502228,875545, 2027193,3963938,8389190,15504996,37555290, 66502859,145809046,292860564,621638120,1156065731, 2701045579] |