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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 24 |
| 5 | 56 |
| 6 | 132 |
| 7 | 312 |
| 8 | 736 |
| 9 | 1736 |
| 10 | 4096 |
| 11 | 9664 |
| 12 | 22800 |
| 13 | 53792 |
| 14 | 126912 |
| 15 | 299424 |
| 16 | 706432 |
| 17 | 1666688 |
| 18 | 3932224 |
| 19 | 9277312 |
| 20 | 21888000 |
| 21 | 51640448 |
| 22 | 121835520 |
| 23 | 287447040 |
| 24 | 678174976 |
| 25 | 1600020992 |
| 26 | 3774936064 |
| 27 | 8906222080 |
| 28 | 21012486144 |
| 29 | 49574844416 |
[1,2,4,10,24,56,132,312,736,1736,4096,9664,22800, 53792,126912,299424,706432,1666688,3932224, 9277312,21888000,51640448,121835520,287447040, 678174976,1600020992,3774936064,8906222080, 21012486144,49574844416] |