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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 48 |
| 5 | 144 |
| 6 | 329 |
| 7 | 2584 |
| 8 | 15456 |
| 9 | 104005 |
| 10 | 832040 |
| 11 | 1866294 |
| 12 | 34111385 |
| 13 | 267914296 |
| 14 | 1602508992 |
| 15 | 10783446409 |
| 16 | 193501094490 |
| 17 | 1548008755920 |
| 18 | 3472236254411 |
| 19 | 166151337293088 |
| 20 | 498454011879264 |
| 21 | 1118049290473933 |
| 22 | 53500214605455696 |
| 23 | 360008399296352015 |
| 24 | 2460986135945634432 |
[1,3,8,48,144,329,2584,15456,104005,832040, 1866294,34111385,267914296,1602508992,10783446409, 193501094490,1548008755920,3472236254411, 166151337293088,498454011879264,1118049290473933, 53500214605455696,360008399296352015, 2460986135945634432] |