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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 37 |
| 4 | 171 |
| 5 | 770 |
| 6 | 3625 |
| 7 | 16924 |
| 8 | 80595 |
| 9 | 382918 |
| 10 | 1837819 |
| 11 | 8819773 |
| 12 | 42571079 |
| 13 | 205627890 |
| 14 | 996794721 |
| 15 | 4836699211 |
| 16 | 23525392935 |
| 17 | 114539663040 |
| 18 | 558627741653 |
| 19 | 2727055503163 |
| 20 | 13329987574645 |
| 21 | 65212629715382 |
| 22 | 319358257652623 |
| 23 | 1565130485339104 |
| 24 | 7676883257129551 |
| 25 | 37679730531468542 |
| 26 | 185068793084335583 |
[1,2,9,37,171,770,3625,16924,80595,382918,1837819, 8819773,42571079,205627890,996794721,4836699211, 23525392935,114539663040,558627741653, 2727055503163,13329987574645,65212629715382, 319358257652623,1565130485339104,7676883257129551, 37679730531468542,185068793084335583] |