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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 14 |
| 5 | 89 |
| 6 | 371 |
| 7 | 2161 |
| 8 | 10696 |
| 9 | 61969 |
| 10 | 335434 |
| 11 | 1952772 |
| 12 | 11086400 |
| 13 | 65242174 |
| 14 | 381110396 |
| 15 | 2268552339 |
| 16 | 13498467880 |
| 17 | 81190422545 |
| 18 | 489403577479 |
| 19 | 2970230729380 |
| 20 | 18078456241060 |
| 21 | 110557602461243 |
| 22 | 678051379830676 |
| 23 | 4173297748385770 |
| 24 | 25753520575460880 |
| 25 | 159374541532819470 |
| 26 | 988579243982587598 |
[1,1,5,14,89,371,2161,10696,61969,335434,1952772, 11086400,65242174,381110396,2268552339, 13498467880,81190422545,489403577479, 2970230729380,18078456241060,110557602461243, 678051379830676,4173297748385770, 25753520575460880,159374541532819470, 988579243982587598] |