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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 44 |
| 4 | 174 |
| 5 | 822 |
| 6 | 3414 |
| 7 | 16604 |
| 8 | 70600 |
| 9 | 348828 |
| 10 | 1503802 |
| 11 | 7504156 |
| 12 | 32645122 |
| 13 | 164014374 |
| 14 | 718098056 |
| 15 | 3625748104 |
| 16 | 15950473396 |
| 17 | 80839381968 |
| 18 | 356946436186 |
| 19 | 1814421022372 |
| 20 | 8035178656538 |
| 21 | 40941855317034 |
| 22 | 181746522965214 |
| 23 | 927880523400340 |
[1,3,10,44,174,822,3414,16604,70600,348828, 1503802,7504156,32645122,164014374,718098056, 3625748104,15950473396,80839381968,356946436186, 1814421022372,8035178656538,40941855317034, 181746522965214,927880523400340] |