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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 25 |
| 6 | 97 |
| 7 | 217 |
| 8 | 872 |
| 9 | 2073 |
| 10 | 8739 |
| 11 | 21791 |
| 12 | 94168 |
| 13 | 242515 |
| 14 | 1052724 |
| 15 | 2768883 |
| 16 | 12208052 |
| 17 | 32759425 |
| 18 | 146062195 |
| 19 | 398210911 |
| 20 | 1784256044 |
| 21 | 4923235527 |
| 22 | 22189335102 |
| 23 | 61880489173 |
| 24 | 280668260110 |
| 25 | 790141842345 |
| 26 | 3597552961167 |
| 27 | 10206542166177 |
| 28 | 46623204529182 |
| 29 | 133170203047901 |
| 30 | 610549741362451 |
| 31 | 1754713551161917 |
[1,1,2,3,12,25,97,217,872,2073,8739,21791,94168, 242515,1052724,2768883,12208052,32759425, 146062195,398210911,1784256044,4923235527, 22189335102,61880489173,280668260110,790141842345, 3597552961167,10206542166177,46623204529182, 133170203047901,610549741362451,1754713551161917] |