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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 221 |
| 10 | 29745 |
| 11 | 3204423 |
| 12 | 307002944 |
| 13 | 27599253281 |
| 14 | 2402068598621 |
| 15 | 206421946595193 |
| 16 | 17745023547769043 |
| 17 | 1539711485029843466 |
| 18 | 135701086522090847679 |
| 19 | 12203103757932310440888 |
[0,0,0,0,0,0,0,0,1,221,29745,3204423,307002944, 27599253281,2402068598621,206421946595193, 17745023547769043,1539711485029843466, 135701086522090847679,12203103757932310440888] |