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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 29 |
| 6 | 98 |
| 7 | 335 |
| 8 | 1316 |
| 9 | 5574 |
| 10 | 26038 |
| 11 | 132771 |
| 12 | 737470 |
| 13 | 4421609 |
| 14 | 28387672 |
| 15 | 193573820 |
| 16 | 1392654721 |
| 17 | 10515499817 |
| 18 | 82994520352 |
| 19 | 682554444859 |
| 20 | 5834509494401 |
| 21 | 51730722356462 |
| 22 | 474894282556542 |
| 23 | 4506807221010963 |
[1,2,4,11,29,98,335,1316,5574,26038,132771,737470, 4421609,28387672,193573820,1392654721,10515499817, 82994520352,682554444859,5834509494401, 51730722356462,474894282556542,4506807221010963] |