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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 25 |
| 3 | 154 |
| 4 | 1590 |
| 5 | 17535 |
| 6 | 763 |
| 7 | 710101 |
| 8 | 22931746 |
| 9 | 24658602 |
| 10 | 386980413 |
| 11 | 15647738229 |
| 12 | 368299898267 |
| 13 | 2164164669333 |
| 14 | 5758910552710 |
| 15 | 46970519777308 |
[1,25,154,1590,17535,763,710101,22931746,24658602, 386980413,15647738229,368299898267,2164164669333, 5758910552710,46970519777308] |