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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 32 |
| 5 | 136 |
| 6 | 722 |
| 7 | 3924 |
| 8 | 22954 |
| 9 | 138316 |
| 10 | 860364 |
| 11 | 5472444 |
| 12 | 35503288 |
| 13 | 234070648 |
| 14 | 1564945158 |
| 15 | 10589356592 |
| 16 | 72412611194 |
| 17 | 499788291616 |
| 18 | 3478059566250 |
| 19 | 24383023246284 |
| 20 | 172074483068320 |
| 21 | 1221654305104920 |
| 22 | 8720583728414354 |
| 23 | 62560709120463028 |
| 24 | 450854177292364660 |
[1,1,3,8,32,136,722,3924,22954,138316,860364, 5472444,35503288,234070648,1564945158,10589356592, 72412611194,499788291616,3478059566250, 24383023246284,172074483068320,1221654305104920, 8720583728414354,62560709120463028, 450854177292364660] |