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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 63 |
| 5 | 251 |
| 6 | 1021 |
| 7 | 4229 |
| 8 | 17763 |
| 9 | 75495 |
| 10 | 324419 |
| 11 | 1405651 |
| 12 | 6129959 |
| 13 | 26885263 |
| 14 | 118546757 |
| 15 | 525145593 |
| 16 | 2335550797 |
| 17 | 10423483181 |
| 18 | 46668994497 |
| 19 | 209568731239 |
| 20 | 943579928523 |
| 21 | 4258648662289 |
| 22 | 19262899227221 |
| 23 | 87309837723849 |
| 24 | 396489947776471 |
| 25 | 1803702183461177 |
| 26 | 8218756170526909 |
| 27 | 37506891842655889 |
[1,1,5,17,63,251,1021,4229,17763,75495,324419, 1405651,6129959,26885263,118546757,525145593, 2335550797,10423483181,46668994497,209568731239, 943579928523,4258648662289,19262899227221, 87309837723849,396489947776471,1803702183461177, 8218756170526909,37506891842655889] |