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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 13 |
| 6 | 57 |
| 7 | 241 |
| 8 | 1493 |
| 9 | 15662 |
| 10 | 167561 |
| 11 | 3201536 |
| 12 | 81713399 |
| 13 | 2408694438 |
| 14 | 99639130001 |
[1,1,1,1,13,57,241,1493,15662,167561,3201536, 81713399,2408694438,99639130001] |