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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 39 |
| 6 | 164 |
| 7 | 746 |
| 8 | 3474 |
| 9 | 16658 |
| 10 | 81166 |
| 11 | 401169 |
| 12 | 2004517 |
| 13 | 10110757 |
| 14 | 51402250 |
| 15 | 263133142 |
| 16 | 1355126922 |
| 17 | 7016115632 |
| 18 | 36498130908 |
| 19 | 190673015083 |
| 20 | 999932115039 |
| 21 | 5262094054524 |
| 22 | 27779114013628 |
| 23 | 147072756065567 |
| 24 | 780722981065006 |
[1,1,3,10,39,164,746,3474,16658,81166,401169, 2004517,10110757,51402250,263133142,1355126922, 7016115632,36498130908,190673015083,999932115039, 5262094054524,27779114013628,147072756065567, 780722981065006] |