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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 9 |
| 7 | 15 |
| 8 | 22 |
| 9 | 30 |
| 10 | 69 |
| 11 | 118 |
| 12 | 178 |
| 13 | 250 |
| 14 | 335 |
| 15 | 769 |
| 16 | 1317 |
| 17 | 1995 |
| 18 | 2820 |
| 19 | 3810 |
| 20 | 4984 |
| 21 | 11346 |
| 22 | 19311 |
| 23 | 29126 |
| 24 | 41061 |
| 25 | 55410 |
| 26 | 72492 |
| 27 | 92652 |
| 28 | 208914 |
| 29 | 352636 |
| 30 | 528097 |
| 31 | 740035 |
| 32 | 993678 |
| 33 | 1294776 |
| 34 | 1649634 |
| 35 | 2065146 |
| 36 | 4613976 |
| 37 | 7722840 |
| 38 | 11476963 |
| 39 | 15971180 |
[1,1,1,2,3,4,9,15,22,30,69,118,178,250,335,769, 1317,1995,2820,3810,4984,11346,19311,29126,41061, 55410,72492,92652,208914,352636,528097,740035, 993678,1294776,1649634,2065146,4613976,7722840, 11476963,15971180] |