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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 15 |
| 5 | 49 |
| 6 | 136 |
| 7 | 446 |
| 8 | 815 |
| 9 | 2045 |
| 10 | 3833 |
| 11 | 8717 |
| 12 | 14272 |
| 13 | 39260 |
| 14 | 72840 |
| 15 | 210072 |
| 16 | 340127 |
| 17 | 791503 |
| 18 | 1695607 |
| 19 | 2740397 |
| 20 | 7948517 |
| 21 | 14258853 |
| 22 | 31589187 |
| 23 | 62871303 |
| 24 | 172680120 |
| 25 | 259553374 |
| 26 | 491879422 |
| 27 | 1390281126 |
| 28 | 3193983644 |
| 29 | 5509013560 |
| 30 | 11070386930 |
| 31 | 27804975886 |
| 32 | 57398653055 |
| 33 | 108014137383 |
[1,1,3,8,15,49,136,446,815,2045,3833,8717,14272, 39260,72840,210072,340127,791503,1695607,2740397, 7948517,14258853,31589187,62871303,172680120, 259553374,491879422,1390281126,3193983644, 5509013560,11070386930,27804975886,57398653055, 108014137383] |