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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 34 |
| 4 | 207 |
| 5 | 1496 |
| 6 | 12420 |
| 7 | 115938 |
| 8 | 1198831 |
| 9 | 13582010 |
| 10 | 167187547 |
| 11 | 2221174504 |
| 12 | 31675372612 |
| 13 | 482628099144 |
| 14 | 7825665501852 |
| 15 | 134562607924194 |
| 16 | 2446051941152127 |
| 17 | 46873289933397206 |
| 18 | 944492559814284397 |
[1,2,7,34,207,1496,12420,115938,1198831,13582010, 167187547,2221174504,31675372612,482628099144, 7825665501852,134562607924194,2446051941152127, 46873289933397206,944492559814284397] |