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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 5 |
| 3 | 24 |
| 4 | 129 |
| 5 | 752 |
| 6 | 4796 |
| 7 | 33117 |
| 8 | 246336 |
| 9 | 1961233 |
| 10 | 16626100 |
| 11 | 149376533 |
| 12 | 1416602126 |
| 13 | 14130107135 |
| 14 | 147781380186 |
| 15 | 1616110614723 |
| 16 | 18434515499407 |
| 17 | 218849548323400 |
| 18 | 2698686223271769 |
| 19 | 34504328470389166 |
| 20 | 456669361749612835 |
| 21 | 6247290917385938422 |
| 22 | 88216873775207493056 |
[0,1,5,24,129,752,4796,33117,246336,1961233, 16626100,149376533,1416602126,14130107135, 147781380186,1616110614723,18434515499407, 218849548323400,2698686223271769, 34504328470389166,456669361749612835, 6247290917385938422,88216873775207493056] |