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| n | a(n) |
|---|---|
| 6 | 1 |
| 7 | 2 |
| 8 | 7 |
| 9 | 22 |
| 10 | 73 |
| 11 | 240 |
| 12 | 818 |
| 13 | 2816 |
| 14 | 9967 |
| 15 | 36080 |
| 16 | 133875 |
| 17 | 509676 |
| 18 | 1990984 |
| 19 | 7990628 |
| 20 | 32936173 |
| 21 | 139548808 |
| 22 | 607402437 |
| 23 | 2716780286 |
| 24 | 12476624346 |
| 25 | 58818236078 |
| 26 | 284350933608 |
| 27 | 1408898449946 |
| 28 | 7146679566822 |
| 29 | 37085526689402 |
| 30 | 196654885016221 |
| 31 | 1064783059174600 |
[1,2,7,22,73,240,818,2816,9967,36080,133875, 509676,1990984,7990628,32936173,139548808, 607402437,2716780286,12476624346,58818236078, 284350933608,1408898449946,7146679566822, 37085526689402,196654885016221,1064783059174600] |