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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 7 |
| 5 | 17 |
| 6 | 75 |
| 7 | 346 |
| 8 | 4874 |
| 9 | 49047 |
| 10 | 3009094 |
| 11 | 69540959 |
| 12 | 19266759978 |
| 13 | 1145861630146 |
| 14 | 1316021940482105 |
| 15 | 231957006949639674 |
| 16 | 1000756528918141445755 |
| 17 | 578298169571294295021140 |
[1,1,2,3,7,17,75,346,4874,49047,3009094,69540959, 19266759978,1145861630146,1316021940482105, 231957006949639674,1000756528918141445755, 578298169571294295021140] |