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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 27 |
| 5 | 73 |
| 6 | 196 |
| 7 | 528 |
| 8 | 1421 |
| 9 | 3825 |
| 10 | 10296 |
| 11 | 27714 |
| 12 | 74599 |
| 13 | 200801 |
| 14 | 540504 |
| 15 | 1454896 |
| 16 | 3916201 |
| 17 | 10541393 |
| 18 | 28374684 |
| 19 | 76377258 |
| 20 | 205587683 |
| 21 | 553388489 |
| 22 | 1489577660 |
| 23 | 4009555040 |
| 24 | 10792677717 |
| 25 | 29051077025 |
| 26 | 78197931824 |
| 27 | 210488462658 |
| 28 | 566580111247 |
| 29 | 1525086070785 |
[1,1,4,10,27,73,196,528,1421,3825,10296,27714, 74599,200801,540504,1454896,3916201,10541393, 28374684,76377258,205587683,553388489,1489577660, 4009555040,10792677717,29051077025,78197931824, 210488462658,566580111247,1525086070785] |