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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 19 |
| 4 | 73 |
| 5 | 241 |
| 6 | 831 |
| 7 | 2787 |
| 8 | 9339 |
| 9 | 31003 |
| 10 | 102373 |
| 11 | 336073 |
| 12 | 1097911 |
| 13 | 3570607 |
| 14 | 11565529 |
| 15 | 37324437 |
| 16 | 120052107 |
| 17 | 384962859 |
| 18 | 1230978093 |
| 19 | 3926097681 |
| 20 | 12492150819 |
| 21 | 39660238779 |
| 22 | 125656218933 |
| 23 | 397360559841 |
| 24 | 1254333690477 |
| 25 | 3952929646701 |
| 26 | 12437932152051 |
[1,1,7,19,73,241,831,2787,9339,31003,102373, 336073,1097911,3570607,11565529,37324437, 120052107,384962859,1230978093,3926097681, 12492150819,39660238779,125656218933,397360559841, 1254333690477,3952929646701,12437932152051] |