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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 21 |
| 4 | 48 |
| 5 | 215 |
| 6 | 798 |
| 7 | 3055 |
| 8 | 9810 |
| 9 | 41744 |
| 10 | 159183 |
| 11 | 570536 |
| 12 | 2308616 |
| 13 | 8872579 |
| 14 | 33367632 |
| 15 | 131450744 |
| 16 | 506761978 |
| 17 | 1940496321 |
| 18 | 7558901654 |
| 19 | 29184688564 |
| 20 | 112473463039 |
| 21 | 436144732416 |
| 22 | 1685260077151 |
| 23 | 6509144124179 |
| 24 | 25196323364937 |
[2,10,21,48,215,798,3055,9810,41744,159183,570536, 2308616,8872579,33367632,131450744,506761978, 1940496321,7558901654,29184688564,112473463039, 436144732416,1685260077151,6509144124179, 25196323364937] |