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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 21 |
| 5 | 66 |
| 6 | 258 |
| 7 | 1079 |
| 8 | 4987 |
| 9 | 25195 |
| 10 | 136723 |
| 11 | 789438 |
| 12 | 4863268 |
| 13 | 31693715 |
| 14 | 217331845 |
| 15 | 1564583770 |
| 16 | 11795630861 |
| 17 | 92833623206 |
| 18 | 760811482322 |
| 19 | 6479991883525 |
| 20 | 57256139503047 |
| 21 | 523919025038279 |
| 22 | 4956976879724565 |
| 23 | 48424420955966635 |
| 24 | 487810283307069696 |
[1,3,7,21,66,258,1079,4987,25195,136723,789438, 4863268,31693715,217331845,1564583770,11795630861, 92833623206,760811482322,6479991883525, 57256139503047,523919025038279,4956976879724565, 48424420955966635,487810283307069696] |