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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 17 |
| 7 | 59 |
| 8 | 104 |
| 9 | 345 |
| 10 | 1199 |
| 11 | 3851 |
| 12 | 12806 |
| 13 | 82134 |
| 14 | 263587 |
| 15 | 1652702 |
| 16 | 10527130 |
| 17 | 63679653 |
| 18 | 393522264 |
| 19 | 4714694321 |
| 20 | 28217205768 |
| 21 | 327320006475 |
| 22 | 3884899169563 |
| 23 | 43662102002059 |
| 24 | 501940164730369 |
| 25 | 11189482352958319 |
| 26 | 124569478026604902 |
[1,2,2,3,5,9,17,59,104,345,1199,3851,12806,82134, 263587,1652702,10527130,63679653,393522264, 4714694321,28217205768,327320006475,3884899169563, 43662102002059,501940164730369,11189482352958319, 124569478026604902] |