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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 59 |
| 5 | 214 |
| 6 | 803 |
| 7 | 3112 |
| 8 | 12175 |
| 9 | 48204 |
| 10 | 193547 |
| 11 | 783625 |
| 12 | 3192053 |
| 13 | 13089520 |
| 14 | 54000289 |
| 15 | 223719067 |
| 16 | 930532505 |
| 17 | 3885596256 |
| 18 | 16278334661 |
| 19 | 68386305015 |
| 20 | 288067637489 |
| 21 | 1216459217496 |
| 22 | 5148025687209 |
| 23 | 21829791198372 |
| 24 | 92742834232835 |
| 25 | 394696063533898 |
| 26 | 1682409396500289 |
| 27 | 7182037203747231 |
[1,2,5,17,59,214,803,3112,12175,48204,193547, 783625,3192053,13089520,54000289,223719067, 930532505,3885596256,16278334661,68386305015, 288067637489,1216459217496,5148025687209, 21829791198372,92742834232835,394696063533898, 1682409396500289,7182037203747231] |