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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 21 |
| 3 | 252 |
| 4 | 1589 |
| 5 | 1022 |
| 6 | 21483 |
| 7 | 17892 |
| 8 | 213402 |
| 9 | 102837 |
| 10 | 147420 |
| 11 | 1445787 |
| 12 | 1707930 |
| 13 | 1711962 |
| 14 | 13667738 |
| 15 | 16092433 |
| 16 | 6589877 |
| 17 | 110132442 |
| 18 | 111443346 |
| 19 | 93093147 |
| 20 | 76545756 |
| 21 | 878996762 |
| 22 | 1029991697 |
| 23 | 874802586 |
| 24 | 421817781 |
| 25 | 1068263553 |
[0,21,252,1589,1022,21483,17892,213402,102837, 147420,1445787,1707930,1711962,13667738,16092433, 6589877,110132442,111443346,93093147,76545756, 878996762,1029991697,874802586,421817781, 1068263553] |