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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 202 |
| 3 | 53768 |
| 4 | 19341130 |
| 5 | 8151741752 |
| 6 | 3795394507240 |
| 7 | 1892725627422240 |
| 8 | 992594962274742090 |
| 9 | 540969426319412656280 |
| 10 | 303934170379321788972952 |
| 11 | 175019302819674622982714912 |
| 12 | 102858166922334018149414066152 |
| 13 | 61493440878115135100772134725088 |
[1,2,202,53768,19341130,8151741752,3795394507240, 1892725627422240,992594962274742090, 540969426319412656280,303934170379321788972952, 175019302819674622982714912, 102858166922334018149414066152, 61493440878115135100772134725088] |