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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 37 |
| 4 | 126 |
| 5 | 431 |
| 6 | 1554 |
| 7 | 5601 |
| 8 | 20036 |
| 9 | 71722 |
| 10 | 256991 |
| 11 | 920643 |
| 12 | 3297782 |
| 13 | 11813230 |
| 14 | 42316775 |
| 15 | 151584446 |
| 16 | 542999656 |
| 17 | 1945111540 |
| 18 | 6967686648 |
| 19 | 24959322680 |
| 20 | 89408160916 |
| 21 | 320273851760 |
| 22 | 1147270357089 |
| 23 | 4109699588023 |
| 24 | 14721578711022 |
[1,8,37,126,431,1554,5601,20036,71722,256991, 920643,3297782,11813230,42316775,151584446, 542999656,1945111540,6967686648,24959322680, 89408160916,320273851760,1147270357089, 4109699588023,14721578711022] |