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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 16 |
| 3 | 229 |
| 4 | 3712 |
| 5 | 61545 |
| 6 | 1026377 |
| 7 | 17224974 |
| 8 | 291563806 |
| 9 | 4984273228 |
| 10 | 86086143903 |
| 11 | 1502219415538 |
[2,16,229,3712,61545,1026377,17224974,291563806, 4984273228,86086143903,1502219415538] |