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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 25 |
| 3 | 219 |
| 4 | 2025 |
| 5 | 19253 |
| 6 | 186469 |
| 7 | 1829565 |
| 8 | 18124521 |
| 9 | 180886260 |
| 10 | 1815946275 |
| 11 | 18318160358 |
| 12 | 185518492965 |
| 13 | 1885157971596 |
| 14 | 19211066004995 |
| 15 | 196258973605094 |
| 16 | 2009302383218409 |
| 17 | 20610411795602760 |
| 18 | 211768072490024440 |
| 19 | 2179156980022097775 |
| 20 | 22454554231950998275 |
[1,3,25,219,2025,19253,186469,1829565,18124521, 180886260,1815946275,18318160358,185518492965, 1885157971596,19211066004995,196258973605094, 2009302383218409,20610411795602760, 211768072490024440,2179156980022097775, 22454554231950998275] |