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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 42 |
| 5 | 126 |
| 6 | 387 |
| 7 | 1180 |
| 8 | 3606 |
| 9 | 11012 |
| 10 | 33636 |
| 11 | 102733 |
| 12 | 313781 |
| 13 | 958384 |
| 14 | 2927209 |
| 15 | 8940617 |
| 16 | 27307465 |
| 17 | 83405605 |
| 18 | 254747014 |
| 19 | 778077690 |
| 20 | 2376494563 |
| 21 | 7258563604 |
| 22 | 22169941574 |
| 23 | 67713990832 |
| 24 | 206819875428 |
| 25 | 631693101321 |
| 26 | 1929389878185 |
[1,1,5,13,42,126,387,1180,3606,11012,33636,102733, 313781,958384,2927209,8940617,27307465,83405605, 254747014,778077690,2376494563,7258563604, 22169941574,67713990832,206819875428,631693101321, 1929389878185] |