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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 6 |
| 4 | 18 |
| 5 | 30 |
| 6 | 87 |
| 7 | 202 |
| 8 | 526 |
| 9 | 1449 |
| 10 | 3893 |
| 11 | 10886 |
| 12 | 30529 |
| 13 | 85878 |
| 14 | 243545 |
| 15 | 691293 |
| 16 | 1966629 |
| 17 | 5603311 |
| 18 | 15974714 |
| 19 | 45572960 |
| 20 | 130060050 |
| 21 | 371260631 |
| 22 | 1059964088 |
| 23 | 3026563164 |
| 24 | 8642492229 |
| 25 | 24680273281 |
| 26 | 70481398248 |
| 27 | 201283524625 |
| 28 | 574841555052 |
[1,7,6,18,30,87,202,526,1449,3893,10886,30529, 85878,243545,691293,1966629,5603311,15974714, 45572960,130060050,371260631,1059964088, 3026563164,8642492229,24680273281,70481398248, 201283524625,574841555052] |