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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 17 |
| 7 | 46 |
| 8 | 124 |
| 9 | 341 |
| 10 | 947 |
| 11 | 2630 |
| 12 | 7299 |
| 13 | 20261 |
| 14 | 56255 |
| 15 | 156198 |
| 16 | 433692 |
| 17 | 1204166 |
| 18 | 3343438 |
| 19 | 9283267 |
| 20 | 25775570 |
| 21 | 71567465 |
| 22 | 198711506 |
| 23 | 551734848 |
| 24 | 1531926101 |
| 25 | 4253488019 |
| 26 | 11810073810 |
| 27 | 32791403883 |
| 28 | 91047370757 |
| 29 | 252798683167 |
[1,2,2,3,6,17,46,124,341,947,2630,7299,20261, 56255,156198,433692,1204166,3343438,9283267, 25775570,71567465,198711506,551734848,1531926101, 4253488019,11810073810,32791403883,91047370757, 252798683167] |