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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 9 |
| 6 | 11 |
| 7 | 82 |
| 8 | 254 |
| 9 | 1669 |
| 10 | 6665 |
| 11 | 68316 |
| 12 | 226521 |
| 13 | 4561686 |
| 14 | 23734103 |
| 15 | 704383992 |
| 16 | 5907579541 |
| 17 | 236178663400 |
| 18 | 2337315883467 |
| 19 | 150056765859689 |
| 20 | 1811327966926780 |
| 21 | 189399759509400492 |
| 22 | 3276661629995792339 |
| 23 | 507766610202105772758 |
[1,1,3,3,9,11,82,254,1669,6665,68316,226521, 4561686,23734103,704383992,5907579541, 236178663400,2337315883467,150056765859689, 1811327966926780,189399759509400492, 3276661629995792339,507766610202105772758] |