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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 11 |
| 3 | 248 |
| 4 | 9968 |
| 5 | 638772 |
| 6 | 60061657 |
| 7 | 7798036000 |
| 8 | 1336715859150 |
| 9 | 292406145227392 |
| 10 | 79483340339739367 |
| 11 | 26280500564448081664 |
| 12 | 10386012861097225139356 |
| 13 | 4834639222955142417477888 |
| 14 | 2618110215141486526589786501 |
| 15 | 1631888040186649673361825042432 |
| 16 | 1159983453675106278249250918734938 |
[1,1,11,248,9968,638772,60061657,7798036000, 1336715859150,292406145227392,79483340339739367, 26280500564448081664,10386012861097225139356, 4834639222955142417477888, 2618110215141486526589786501, 1631888040186649673361825042432, 1159983453675106278249250918734938] |