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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 11 |
| 8 | 23 |
| 9 | 46 |
| 10 | 104 |
| 11 | 230 |
| 12 | 539 |
| 13 | 1270 |
| 14 | 3081 |
| 15 | 7536 |
| 16 | 18785 |
| 17 | 47207 |
| 18 | 120074 |
| 19 | 307739 |
| 20 | 795426 |
| 21 | 2069248 |
| 22 | 5418014 |
| 23 | 14263084 |
| 24 | 37742929 |
| 25 | 100331646 |
| 26 | 267854040 |
| 27 | 717863832 |
| 28 | 1930888297 |
| 29 | 5210968114 |
| 30 | 14106844554 |
[1,1,1,1,2,3,6,11,23,46,104,230,539,1270,3081, 7536,18785,47207,120074,307739,795426,2069248, 5418014,14263084,37742929,100331646,267854040, 717863832,1930888297,5210968114,14106844554] |