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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 43 |
| 5 | 268 |
| 6 | 1831 |
| 7 | 13354 |
| 8 | 102352 |
| 9 | 816241 |
| 10 | 6728037 |
| 11 | 57056328 |
| 12 | 496185294 |
| 13 | 4414563737 |
| 14 | 40114493041 |
| 15 | 371845437684 |
| 16 | 3513262944971 |
| 17 | 33815076029376 |
| 18 | 331454445914861 |
| 19 | 3308183361941640 |
| 20 | 33620505978224843 |
| 21 | 347942136527114740 |
| 22 | 3667458554727506170 |
| 23 | 39378668472879902163 |
| 24 | 430803711668467138362 |
| 25 | 4802830669726993050928 |
| 26 | 54572510428547279296599 |
[1,1,2,8,43,268,1831,13354,102352,816241,6728037, 57056328,496185294,4414563737,40114493041, 371845437684,3513262944971,33815076029376, 331454445914861,3308183361941640, 33620505978224843,347942136527114740, 3667458554727506170,39378668472879902163, 430803711668467138362,4802830669726993050928, 54572510428547279296599] |