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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 105 |
| 6 | 2625 |
| 7 | 42075 |
| 8 | 554820 |
| 9 | 6578550 |
| 10 | 73169250 |
| 11 | 781319370 |
| 12 | 8122058850 |
| 13 | 82922497890 |
| 14 | 836339477160 |
| 15 | 8366154130425 |
| 16 | 83235403604220 |
| 17 | 825247074255735 |
| 18 | 8165187992777430 |
| 19 | 80704316324506860 |
| 20 | 797435573602269015 |
| 21 | 7881226621071221625 |
| 22 | 77939438593071188565 |
[0,0,0,0,105,2625,42075,554820,6578550,73169250, 781319370,8122058850,82922497890,836339477160, 8366154130425,83235403604220,825247074255735, 8165187992777430,80704316324506860, 797435573602269015,7881226621071221625, 77939438593071188565] |