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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 70 |
| 6 | 349 |
| 7 | 1658 |
| 8 | 7356 |
| 9 | 30374 |
| 10 | 121676 |
| 11 | 479589 |
| 12 | 1917853 |
| 13 | 7777174 |
| 14 | 31840851 |
| 15 | 130793340 |
| 16 | 537219555 |
| 17 | 2200344721 |
| 18 | 8992050521 |
| 19 | 36701192008 |
| 20 | 149773458903 |
| 21 | 611384304706 |
| 22 | 2496957012448 |
| 23 | 10201222295479 |
| 24 | 41681902590078 |
[1,2,5,17,70,349,1658,7356,30374,121676,479589, 1917853,7777174,31840851,130793340,537219555, 2200344721,8992050521,36701192008,149773458903, 611384304706,2496957012448,10201222295479, 41681902590078] |