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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 26 |
| 4 | 18 |
| 5 | 482 |
| 6 | 266 |
| 7 | 6050 |
| 8 | 3114 |
| 9 | 21122 |
| 10 | 10730 |
| 11 | 22178 |
| 12 | 11226 |
| 13 | 4455362 |
| 14 | 2256338 |
| 15 | 343874 |
| 16 | 173610 |
| 17 | 13643522 |
| 18 | 6869842 |
| 19 | 690621122 |
| 20 | 347772738 |
| 21 | 16250361602 |
| 22 | 8187307306 |
| 23 | 17146915106 |
| 24 | 8584448890 |
| 25 | 720152334722 |
| 26 | 365024665978 |
| 27 | 59381983394 |
| 28 | 29700003082 |
[1,2,4,26,18,482,266,6050,3114,21122,10730,22178, 11226,4455362,2256338,343874,173610,13643522, 6869842,690621122,347772738,16250361602, 8187307306,17146915106,8584448890,720152334722, 365024665978,59381983394,29700003082] |