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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 16 |
| 4 | 39 |
| 5 | 55 |
| 6 | 94 |
| 7 | 431 |
| 8 | 10869 |
| 9 | 43907 |
| 10 | 54776 |
| 11 | 98683 |
| 12 | 252142 |
| 13 | 602967 |
| 14 | 2061043 |
| 15 | 4725053 |
| 16 | 238313693 |
| 17 | 481352439 |
| 18 | 1682371010 |
| 19 | 3846094459 |
| 20 | 9374559928 |
| 21 | 13220654387 |
| 22 | 22595214315 |
| 23 | 103601511647 |
| 24 | 2612633005490 |
| 25 | 10554133533607 |
| 26 | 13166766539097 |
[1,2,7,16,39,55,94,431,10869,43907,54776,98683, 252142,602967,2061043,4725053,238313693,481352439, 1682371010,3846094459,9374559928,13220654387, 22595214315,103601511647,2612633005490, 10554133533607,13166766539097] |