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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 93 |
| 6 | 437 |
| 7 | 2233 |
| 8 | 12227 |
| 9 | 71011 |
| 10 | 434151 |
| 11 | 2778424 |
| 12 | 18530560 |
| 13 | 128351696 |
| 14 | 920714033 |
| 15 | 6824472471 |
| 16 | 52169690544 |
| 17 | 410668022430 |
| 18 | 3324392442855 |
| 19 | 27643496374175 |
| 20 | 235891305666644 |
| 21 | 2063970414061799 |
| 22 | 18503192136038026 |
| 23 | 169846619393391680 |
| 24 | 1595434723902554826 |
[1,1,2,6,22,93,437,2233,12227,71011,434151, 2778424,18530560,128351696,920714033,6824472471, 52169690544,410668022430,3324392442855, 27643496374175,235891305666644,2063970414061799, 18503192136038026,169846619393391680, 1595434723902554826] |