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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 241 |
| 2 | 9361 |
| 3 | 131041 |
| 4 | 996001 |
| 5 | 5109841 |
| 6 | 20015281 |
| 7 | 64495681 |
| 8 | 179375041 |
| 9 | 444798001 |
| 10 | 1006201681 |
| 11 | 2111519521 |
| 12 | 4162485601 |
| 13 | 7783236241 |
| 14 | 13909734001 |
| 15 | 23903867521 |
| 16 | 39696408961 |
| 17 | 63963339121 |
| 18 | 100340378641 |
| 19 | 153680892001 |
[1,241,9361,131041,996001,5109841,20015281, 64495681,179375041,444798001,1006201681, 2111519521,4162485601,7783236241,13909734001, 23903867521,39696408961,63963339121,100340378641, 153680892001] |