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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 25 |
| 3 | 115 |
| 4 | 500 |
| 5 | 2092 |
| 6 | 8512 |
| 7 | 33910 |
| 8 | 132892 |
| 9 | 514079 |
| 10 | 1968021 |
| 11 | 7470434 |
| 12 | 28160354 |
| 13 | 105542777 |
| 14 | 393672627 |
| 15 | 1462503264 |
| 16 | 5414896000 |
| 17 | 19991387639 |
| 18 | 73628208598 |
| 19 | 270614786791 |
| 20 | 992880076249 |
| 21 | 3637400475618 |
| 22 | 13308475404934 |
| 23 | 48639360355243 |
| 24 | 177597694845849 |
[1,5,25,115,500,2092,8512,33910,132892,514079, 1968021,7470434,28160354,105542777,393672627, 1462503264,5414896000,19991387639,73628208598, 270614786791,992880076249,3637400475618, 13308475404934,48639360355243,177597694845849] |