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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 49 |
| 5 | 177 |
| 6 | 667 |
| 7 | 2543 |
| 8 | 10041 |
| 9 | 39539 |
| 10 | 158109 |
| 11 | 639433 |
| 12 | 2601015 |
| 13 | 10639159 |
| 14 | 43850367 |
| 15 | 181446123 |
| 16 | 753443505 |
| 17 | 3143865503 |
| 18 | 13160935401 |
| 19 | 55241186593 |
| 20 | 232610710411 |
| 21 | 981971030779 |
| 22 | 4153731301811 |
| 23 | 17610884293985 |
| 24 | 74817976680219 |
| 25 | 318387365734597 |
| 26 | 1357252694442173 |
| 27 | 5795165115392909 |
[1,1,5,13,49,177,667,2543,10041,39539,158109, 639433,2601015,10639159,43850367,181446123, 753443505,3143865503,13160935401,55241186593, 232610710411,981971030779,4153731301811, 17610884293985,74817976680219,318387365734597, 1357252694442173,5795165115392909] |