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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 115 |
| 4 | 483 |
| 5 | 7148 |
| 6 | 24779 |
| 7 | 295813 |
| 8 | 804538 |
| 9 | 7711613 |
| 10 | 17135660 |
| 11 | 137991357 |
| 12 | 261853930 |
| 13 | 1838296465 |
| 14 | 3078156753 |
| 15 | 19352193027 |
| 16 | 29273561002 |
| 17 | 168059197372 |
| 18 | 233637796573 |
| 19 | 1242746736360 |
| 20 | 1608517392555 |
| 21 | 8015798428649 |
| 22 | 9756858004272 |
[2,9,115,483,7148,24779,295813,804538,7711613, 17135660,137991357,261853930,1838296465, 3078156753,19352193027,29273561002,168059197372, 233637796573,1242746736360,1608517392555, 8015798428649,9756858004272] |