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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 18 |
| 4 | 47 |
| 5 | 123 |
| 6 | 328 |
| 7 | 886 |
| 8 | 2419 |
| 9 | 6675 |
| 10 | 18587 |
| 11 | 52164 |
| 12 | 147404 |
| 13 | 418991 |
| 14 | 1197002 |
| 15 | 3434568 |
| 16 | 9891715 |
| 17 | 28580469 |
| 18 | 82808899 |
| 19 | 240511642 |
| 20 | 700024987 |
| 21 | 2041255981 |
| 22 | 5962023006 |
| 23 | 17439034426 |
| 24 | 51075928264 |
| 25 | 149767494573 |
| 26 | 439619556301 |
| 27 | 1291671623988 |
| 28 | 3798447661874 |
| 29 | 11179106282223 |
| 30 | 32925086562548 |
[1,3,7,18,47,123,328,886,2419,6675,18587,52164, 147404,418991,1197002,3434568,9891715,28580469, 82808899,240511642,700024987,2041255981, 5962023006,17439034426,51075928264,149767494573, 439619556301,1291671623988,3798447661874, 11179106282223,32925086562548] |