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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 13 |
| 4 | 23 |
| 5 | 61 |
| 6 | 177 |
| 7 | 444 |
| 8 | 1325 |
| 9 | 3716 |
| 10 | 8186 |
| 11 | 18168 |
| 12 | 62025 |
| 13 | 275360 |
| 14 | 461299 |
| 15 | 498201 |
[1,4,13,23,61,177,444,1325,3716,8186,18168,62025, 275360,461299,498201] |