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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 44 |
| 4 | 256 |
| 5 | 1512 |
| 6 | 9056 |
| 7 | 54896 |
| 8 | 335872 |
| 9 | 2069774 |
| 10 | 12827888 |
| 11 | 79875996 |
| 12 | 499305472 |
| 13 | 3131436856 |
| 14 | 19694403520 |
| 15 | 124165133424 |
| 16 | 784478240768 |
| 17 | 4965659813668 |
| 18 | 31484486937512 |
| 19 | 199923173603596 |
| 20 | 1271192603065856 |
| 21 | 8092551782518688 |
| 22 | 51574780342740256 |
| 23 | 329022223268286288 |
| 24 | 2100934234342260736 |
[1,2,8,44,256,1512,9056,54896,335872,2069774, 12827888,79875996,499305472,3131436856, 19694403520,124165133424,784478240768, 4965659813668,31484486937512,199923173603596, 1271192603065856,8092551782518688, 51574780342740256,329022223268286288, 2100934234342260736] |