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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 8 |
| 5 | 4 |
| 6 | 16 |
| 7 | 24 |
| 8 | 60 |
| 9 | 140 |
| 10 | 1328 |
| 11 | 2144 |
| 12 | 17536 |
| 13 | 23296 |
| 14 | 74216 |
| 15 | 191544 |
| 16 | 2119632 |
| 17 | 4094976 |
| 18 | 24223424 |
| 19 | 45604056 |
| 20 | 241559918 |
| 21 | 675603568 |
| 22 | 8723487720 |
| 23 | 22850057800 |
| 24 | 285146572432 |
| 25 | 859834538938 |
| 26 | 8276479696196 |
| 27 | 32343039694056 |
| 28 | 429691823372130 |
[1,2,2,8,4,16,24,60,140,1328,2144,17536,23296, 74216,191544,2119632,4094976,24223424,45604056, 241559918,675603568,8723487720,22850057800, 285146572432,859834538938,8276479696196, 32343039694056,429691823372130] |