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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 14 |
| 3 | 61 |
| 4 | 263 |
| 5 | 1128 |
| 6 | 4788 |
| 7 | 20271 |
| 8 | 85885 |
| 9 | 364408 |
| 10 | 1546394 |
| 11 | 6563924 |
| 12 | 27863816 |
| 13 | 118286561 |
[3,14,61,263,1128,4788,20271,85885,364408,1546394, 6563924,27863816,118286561] |