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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 6 |
| 7 | 96 |
| 8 | 130 |
| 9 | 4930 |
| 10 | 6556 |
| 11 | 416615 |
| 12 | 547035 |
| 13 | 52346851 |
| 14 | 68052947 |
| 15 | 9150486666 |
| 16 | 11800704395 |
| 17 | 2122773858331 |
| 18 | 2719323939675 |
| 19 | 630854176216923 |
| 20 | 803548959057850 |
| 21 | 233667907156182198 |
| 22 | 296168864567954970 |
| 23 | 105531126177212999940 |
| 24 | 133179680978969198101 |
| 25 | 57078667671269237092154 |
[0,0,1,1,4,6,96,130,4930,6556,416615,547035, 52346851,68052947,9150486666,11800704395, 2122773858331,2719323939675,630854176216923, 803548959057850,233667907156182198, 296168864567954970,105531126177212999940, 133179680978969198101,57078667671269237092154] |