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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 27 |
| 6 | 62 |
| 7 | 144 |
| 8 | 336 |
| 9 | 790 |
| 10 | 1870 |
| 11 | 4452 |
| 12 | 10656 |
| 13 | 25629 |
| 14 | 61910 |
| 15 | 150145 |
| 16 | 365450 |
| 17 | 892434 |
| 18 | 2185928 |
| 19 | 5369097 |
| 20 | 13221422 |
| 21 | 32634935 |
| 22 | 80730942 |
| 23 | 200116410 |
| 24 | 496992992 |
| 25 | 1236482727 |
| 26 | 3081389406 |
| 27 | 7690966549 |
| 28 | 19224282880 |
| 29 | 48119034729 |
| 30 | 120599916654 |
[1,2,5,12,27,62,144,336,790,1870,4452,10656,25629, 61910,150145,365450,892434,2185928,5369097, 13221422,32634935,80730942,200116410,496992992, 1236482727,3081389406,7690966549,19224282880, 48119034729,120599916654] |