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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 51 |
| 5 | 181 |
| 6 | 603 |
| 7 | 1933 |
| 8 | 6051 |
| 9 | 18661 |
| 10 | 57003 |
| 11 | 173053 |
| 12 | 523251 |
| 13 | 1577941 |
| 14 | 4750203 |
| 15 | 14283373 |
| 16 | 42915651 |
| 17 | 128878021 |
| 18 | 386896203 |
| 19 | 1161212893 |
| 20 | 3484687251 |
| 21 | 10456158901 |
| 22 | 31372671003 |
| 23 | 94126401613 |
| 24 | 282395982051 |
| 25 | 847221500581 |
[1,1,3,13,51,181,603,1933,6051,18661,57003,173053, 523251,1577941,4750203,14283373,42915651, 128878021,386896203,1161212893,3484687251, 10456158901,31372671003,94126401613,282395982051, 847221500581] |