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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 1 |
| 4 | 5 |
| 5 | 21 |
| 6 | 86 |
| 7 | 361 |
| 8 | 1584 |
| 9 | 7315 |
| 10 | 35635 |
| 11 | 183080 |
| 12 | 990659 |
| 13 | 5635021 |
| 14 | 33622161 |
| 15 | 209973099 |
| 16 | 1369560267 |
| 17 | 9310957518 |
| 18 | 65852852210 |
| 19 | 483672626464 |
| 20 | 3683088047043 |
| 21 | 29033382412670 |
| 22 | 236591717703447 |
| 23 | 1990467019391404 |
| 24 | 17268021545339042 |
| 25 | 154304401318961489 |
[0,1,5,21,86,361,1584,7315,35635,183080,990659, 5635021,33622161,209973099,1369560267,9310957518, 65852852210,483672626464,3683088047043, 29033382412670,236591717703447,1990467019391404, 17268021545339042,154304401318961489] |