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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 8 |
| 5 | 8 |
| 6 | 132 |
| 7 | 272 |
| 8 | 1844 |
| 9 | 7824 |
| 10 | 219392 |
| 11 | 879040 |
| 12 | 9865488 |
| 13 | 30363264 |
| 14 | 1348905760 |
| 15 | 26759363296 |
| 16 | 265338415104 |
| 17 | 1871331759456 |
| 18 | 24675601835904 |
| 19 | 166652846570112 |
| 20 | 1969110048305664 |
| 21 | 22090834149738048 |
| 22 | 2586719545294006272 |
| 23 | 22961806952814951168 |
| 24 | 289429435718440962048 |
[1,1,2,2,8,8,132,272,1844,7824,219392,879040, 9865488,30363264,1348905760,26759363296, 265338415104,1871331759456,24675601835904, 166652846570112,1969110048305664, 22090834149738048,2586719545294006272, 22961806952814951168,289429435718440962048] |