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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 18 |
| 5 | 102 |
| 6 | 949 |
| 7 | 14731 |
| 8 | 386060 |
| 9 | 17323052 |
| 10 | 1351157580 |
| 11 | 185867701560 |
| 12 | 45682244004244 |
| 13 | 20283964291276804 |
| 14 | 16423005586691362832 |
| 15 | 24434416299840231799694 |
| 16 | 67236458264587977465709983 |
[1,1,2,5,18,102,949,14731,386060,17323052, 1351157580,185867701560,45682244004244, 20283964291276804,16423005586691362832, 24434416299840231799694, 67236458264587977465709983] |