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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 37 |
| 7 | 63 |
| 8 | 478 |
| 9 | 1316 |
| 10 | 8594 |
| 11 | 14619 |
| 12 | 155961 |
| 13 | 211231 |
| 14 | 1732844 |
| 15 | 5302820 |
| 16 | 21559430 |
| 17 | 43398413 |
| 18 | 466493982 |
| 19 | 625545865 |
| 20 | 5659491433 |
| 21 | 15126813702 |
| 22 | 72778010746 |
| 23 | 132561145173 |
| 24 | 1460519397614 |
| 25 | 2338565021379 |
[0,0,0,1,3,37,63,478,1316,8594,14619,155961, 211231,1732844,5302820,21559430,43398413, 466493982,625545865,5659491433,15126813702, 72778010746,132561145173,1460519397614, 2338565021379] |