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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 1 |
| 8 | 11 |
| 9 | 125 |
| 10 | 1351 |
| 11 | 15330 |
| 12 | 184846 |
| 13 | 2382084 |
| 14 | 32795170 |
| 15 | 481379278 |
| 16 | 7513591430 |
| 17 | 124363961357 |
| 18 | 2176990766569 |
| 19 | 40199252548280 |
| 20 | 781143277669538 |
| 21 | 15937382209774353 |
| 22 | 340696424417421213 |
| 23 | 7616192835573406931 |
| 24 | 177723017354688250713 |
| 25 | 4321711817908214684734 |
[0,0,0,0,0,0,1,11,125,1351,15330,184846,2382084, 32795170,481379278,7513591430,124363961357, 2176990766569,40199252548280,781143277669538, 15937382209774353,340696424417421213, 7616192835573406931,177723017354688250713, 4321711817908214684734] |