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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 7 |
| 9 | 15 |
| 10 | 27 |
| 11 | 47 |
| 12 | 145 |
| 13 | 629 |
| 14 | 2639 |
| 15 | 10689 |
| 16 | 40727 |
| 17 | 200517 |
| 18 | 1226295 |
| 19 | 9011761 |
| 20 | 67694903 |
| 21 | 542738577 |
| 22 | 4721537297 |
| 23 | 50165476303 |
| 24 | 597630948157 |
[1,1,1,1,1,1,3,7,15,27,47,145,629,2639,10689, 40727,200517,1226295,9011761,67694903,542738577, 4721537297,50165476303,597630948157] |