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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 62 |
| 4 | 394 |
| 5 | 2552 |
| 6 | 16810 |
| 7 | 112114 |
| 8 | 754698 |
| 9 | 5116832 |
| 10 | 34891260 |
| 11 | 239036470 |
| 12 | 1644001546 |
| 13 | 11344059092 |
| 14 | 78497737370 |
| 15 | 544507428962 |
| 16 | 3785080540682 |
| 17 | 26360971309824 |
| 18 | 183895618774084 |
| 19 | 1284778549054704 |
| 20 | 8988079638054044 |
| 21 | 62955181189933276 |
| 22 | 441442177486335002 |
[1,2,10,62,394,2552,16810,112114,754698,5116832, 34891260,239036470,1644001546,11344059092, 78497737370,544507428962,3785080540682, 26360971309824,183895618774084,1284778549054704, 8988079638054044,62955181189933276, 441442177486335002] |