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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 21 |
| 8 | 610 |
| 9 | 514229 |
| 10 | 225851433717 |
| 11 | 16641027750620563662096 |
| 12 | 13180872826374098837632191485015125807374171 |
| 13 | 284812298108489611757988937681460995615380088782304890986477195645969271404032323901 |
[0,0,0,1,1,1,3,21,610,514229,225851433717, 16641027750620563662096, 13180872826374098837632191485015125807374171, 28481229810848961175798893768146099561538008878230\ 4890986477195645969271404032323901] |