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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 44 |
| 5 | 224 |
| 6 | 1345 |
| 7 | 9415 |
| 8 | 75327 |
| 9 | 677949 |
| 10 | 6779490 |
| 11 | 74574400 |
| 12 | 894892802 |
| 13 | 11633606436 |
| 14 | 162870490110 |
| 15 | 2443057351653 |
| 16 | 39088917626459 |
| 17 | 664511599649816 |
| 18 | 11961208793696693 |
| 19 | 227262967080237169 |
| 20 | 4545259341604743382 |
[1,3,11,44,224,1345,9415,75327,677949,6779490, 74574400,894892802,11633606436,162870490110, 2443057351653,39088917626459,664511599649816, 11961208793696693,227262967080237169, 4545259341604743382] |