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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 8 |
| 3 | 8 |
| 4 | 75 |
| 5 | 230 |
| 6 | 1144 |
| 7 | 4263 |
| 8 | 18517 |
| 9 | 75262 |
| 10 | 317141 |
| 11 | 1307739 |
| 12 | 5446889 |
| 13 | 22584896 |
| 14 | 93917334 |
| 15 | 389965508 |
| 16 | 1620245230 |
| 17 | 6729536166 |
| 18 | 27956779018 |
| 19 | 116131464818 |
| 20 | 482427395426 |
| 21 | 2004019363266 |
| 22 | 8324893628475 |
| 23 | 34582253578090 |
| 24 | 143657911533546 |
[0,8,8,75,230,1144,4263,18517,75262,317141, 1307739,5446889,22584896,93917334,389965508, 1620245230,6729536166,27956779018,116131464818, 482427395426,2004019363266,8324893628475, 34582253578090,143657911533546] |