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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 25 |
| 5 | 92 |
| 6 | 369 |
| 7 | 1626 |
| 8 | 8033 |
| 9 | 42312 |
| 10 | 230081 |
| 11 | 1354190 |
| 12 | 8806769 |
| 13 | 59072860 |
| 14 | 398252833 |
| 15 | 2892141666 |
| 16 | 22862362049 |
| 17 | 182200364944 |
| 18 | 1492258801793 |
| 19 | 13163090657814 |
| 20 | 111357664397265 |
| 21 | 938233188787748 |
| 22 | 11338336523834337 |
[1,1,3,8,25,92,369,1626,8033,42312,230081,1354190, 8806769,59072860,398252833,2892141666,22862362049, 182200364944,1492258801793,13163090657814, 111357664397265,938233188787748,11338336523834337] |