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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 22 |
| 4 | 421 |
| 5 | 15806 |
| 6 | 965599 |
| 7 | 86783908 |
| 8 | 10762423433 |
| 9 | 1760139839890 |
| 10 | 366963132246211 |
| 11 | 94986120910852304 |
| 12 | 29885092163103515053 |
| 13 | 11231861500887280969678 |
| 14 | 4969797579946642622052455 |
| 15 | 2557170899273715656424860716 |
| 16 | 1513955937348335077112132690449 |
| 17 | 1021885751416723450814790851481098 |
[1,3,22,421,15806,965599,86783908,10762423433, 1760139839890,366963132246211,94986120910852304, 29885092163103515053,11231861500887280969678, 4969797579946642622052455, 2557170899273715656424860716, 1513955937348335077112132690449, 1021885751416723450814790851481098] |