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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 49 |
| 7 | 10010 |
| 8 | 413727 |
| 9 | 8363578 |
| 10 | 108576799 |
| 11 | 1030757941 |
| 12 | 7721414278 |
| 13 | 47957203600 |
| 14 | 255640086696 |
| 15 | 1199509369309 |
| 16 | 5050244459572 |
| 17 | 19366840027021 |
| 18 | 68459296434321 |
| 19 | 225242952960337 |
| 20 | 695338409837163 |
| 21 | 2027581798386055 |
[0,0,0,0,0,49,10010,413727,8363578,108576799, 1030757941,7721414278,47957203600,255640086696, 1199509369309,5050244459572,19366840027021, 68459296434321,225242952960337,695338409837163, 2027581798386055] |