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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 46 |
| 6 | 201 |
| 7 | 928 |
| 8 | 4399 |
| 9 | 21431 |
| 10 | 106399 |
| 11 | 536896 |
| 12 | 2744532 |
| 13 | 14185314 |
| 14 | 73999955 |
| 15 | 389131156 |
| 16 | 2060478226 |
| 17 | 10976863244 |
| 18 | 58792036053 |
| 19 | 316397505099 |
| 20 | 1710037259744 |
| 21 | 9277953713444 |
| 22 | 50514377326158 |
| 23 | 275903656802218 |
| 24 | 1511334791637679 |
| 25 | 8300811367229306 |
| 26 | 45703063861360901 |
[1,1,3,11,46,201,928,4399,21431,106399,536896, 2744532,14185314,73999955,389131156,2060478226, 10976863244,58792036053,316397505099, 1710037259744,9277953713444,50514377326158, 275903656802218,1511334791637679,8300811367229306, 45703063861360901] |