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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 35 |
| 6 | 210 |
| 7 | 1596 |
| 8 | 12992 |
| 9 | 118863 |
| 10 | 1202870 |
| 11 | 13361392 |
| 12 | 161638752 |
| 13 | 2115684259 |
| 14 | 29792671818 |
| 15 | 449145795900 |
| 16 | 7217975402752 |
| 17 | 123180993414207 |
| 18 | 2224874726830638 |
| 19 | 42402252681323840 |
| 20 | 850380681002034880 |
| 21 | 17902407539998807875 |
| 22 | 394741856473979171586 |
| 23 | 9097740802923890621468 |
[0,0,0,0,35,210,1596,12992,118863,1202870, 13361392,161638752,2115684259,29792671818, 449145795900,7217975402752,123180993414207, 2224874726830638,42402252681323840, 850380681002034880,17902407539998807875, 394741856473979171586,9097740802923890621468] |