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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 37 |
| 4 | 142 |
| 5 | 558 |
| 6 | 2212 |
| 7 | 8811 |
| 8 | 35170 |
| 9 | 140538 |
| 10 | 561868 |
| 11 | 2246914 |
| 12 | 8986540 |
| 13 | 35943948 |
| 14 | 143771368 |
| 15 | 575076661 |
| 16 | 2300289022 |
| 17 | 9201120918 |
| 18 | 36804413332 |
| 19 | 147217512790 |
| 20 | 588869770084 |
| 21 | 2355478518468 |
| 22 | 9421912950136 |
| 23 | 37687649553630 |
[1,3,10,37,142,558,2212,8811,35170,140538,561868, 2246914,8986540,35943948,143771368,575076661, 2300289022,9201120918,36804413332,147217512790, 588869770084,2355478518468,9421912950136, 37687649553630] |