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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 67 |
| 4 | 2941 |
| 5 | 327868 |
| 6 | 75504909 |
| 7 | 23827165139 |
| 8 | 14250056009694 |
| 9 | 12425294009958329 |
| 10 | 14645969719539739213 |
| 11 | 26039632087532302145593 |
| 12 | 61861506372519998418244631 |
| 13 | 188885323588779065057458593218 |
[1,1,2,67,2941,327868,75504909,23827165139, 14250056009694,12425294009958329, 14645969719539739213,26039632087532302145593, 61861506372519998418244631, 188885323588779065057458593218] |