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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 1 |
| 3 | 7 |
| 4 | 1 |
| 5 | 15 |
| 6 | 41 |
| 7 | 127 |
| 8 | 1 |
| 9 | 15 |
| 10 | 41 |
| 11 | 255 |
| 12 | 513 |
| 13 | 3599 |
| 14 | 8745 |
| 15 | 28415 |
| 16 | 1 |
| 17 | 15 |
| 18 | 2601 |
| 19 | 14079 |
| 20 | 32769 |
| 21 | 229391 |
| 22 | 557097 |
| 23 | 3899647 |
| 24 | 9077249 |
| 25 | 28675599 |
| 26 | 10267177 |
| 27 | 64446207 |
| 28 | 171294721 |
| 29 | 513295375 |
| 30 | 30006313 |
| 31 | 209458431 |
| 32 | 657780225 |
| 33 | 4052658703 |
| 34 | 9070269993 |
| 35 | 26967728895 |
[1,3,1,7,1,15,41,127,1,15,41,255,513,3599,8745, 28415,1,15,2601,14079,32769,229391,557097,3899647, 9077249,28675599,10267177,64446207,171294721, 513295375,30006313,209458431,657780225,4052658703, 9070269993,26967728895] |