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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 71 |
| 5 | 297 |
| 6 | 1301 |
| 7 | 5723 |
| 8 | 25809 |
| 9 | 117441 |
| 10 | 539487 |
| 11 | 2497203 |
| 12 | 11641745 |
| 13 | 54540565 |
| 14 | 256723897 |
| 15 | 1213481451 |
| 16 | 5755777471 |
| 17 | 27383682569 |
| 18 | 130648021511 |
| 19 | 624862345197 |
| 20 | 2995106483281 |
| 21 | 14385115772833 |
| 22 | 69216330388613 |
| 23 | 333594136086683 |
| 24 | 1610226943470809 |
| 25 | 7783322584383833 |
| 26 | 37670523046306671 |
| 27 | 182538800744367371 |
[1,1,5,17,71,297,1301,5723,25809,117441,539487, 2497203,11641745,54540565,256723897,1213481451, 5755777471,27383682569,130648021511,624862345197, 2995106483281,14385115772833,69216330388613, 333594136086683,1610226943470809,7783322584383833, 37670523046306671,182538800744367371] |