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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 8 |
| 8 | 23 |
| 9 | 63 |
| 10 | 191 |
| 11 | 685 |
| 12 | 3493 |
| 13 | 20460 |
| 14 | 144341 |
| 15 | 1163965 |
| 16 | 10657560 |
| 17 | 110643922 |
| 18 | 1393408349 |
| 19 | 20934516013 |
| 20 | 373325933993 |
| 21 | 7839237276478 |
| 22 | 192639728351279 |
| 23 | 5496880042565859 |
[1,1,1,1,1,3,8,23,63,191,685,3493,20460,144341, 1163965,10657560,110643922,1393408349,20934516013, 373325933993,7839237276478,192639728351279, 5496880042565859] |