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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 34 |
| 4 | 146 |
| 5 | 628 |
| 6 | 2703 |
| 7 | 11632 |
| 8 | 50057 |
| 9 | 215415 |
| 10 | 927016 |
| 11 | 3989317 |
| 12 | 17167612 |
| 13 | 73879038 |
| 14 | 317930779 |
| 15 | 1368182139 |
| 16 | 5887829959 |
| 17 | 25337665679 |
| 18 | 109038016813 |
| 19 | 469233798454 |
| 20 | 2019298993572 |
| 21 | 8689843823858 |
| 22 | 37395841786394 |
| 23 | 160929127296116 |
| 24 | 692541811472532 |
[1,2,8,34,146,628,2703,11632,50057,215415,927016, 3989317,17167612,73879038,317930779,1368182139, 5887829959,25337665679,109038016813,469233798454, 2019298993572,8689843823858,37395841786394, 160929127296116,692541811472532] |