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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 11 |
| 5 | 24 |
| 6 | 52 |
| 7 | 113 |
| 8 | 248 |
| 9 | 553 |
| 10 | 1245 |
| 11 | 2828 |
| 12 | 6481 |
| 13 | 14963 |
| 14 | 34770 |
| 15 | 81253 |
| 16 | 190836 |
| 17 | 450202 |
| 18 | 1066269 |
| 19 | 2534269 |
| 20 | 6042375 |
| 21 | 14447465 |
| 22 | 34632759 |
[1,2,6,11,24,52,113,248,553,1245,2828,6481,14963, 34770,81253,190836,450202,1066269,2534269,6042375, 14447465,34632759] |