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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 7 |
| 4 | 20 |
| 5 | 15 |
| 6 | 88 |
| 7 | 47 |
| 8 | 272 |
| 9 | 31 |
| 10 | 2016 |
| 11 | 63 |
| 12 | 1600 |
| 13 | 8575 |
| 14 | 384 |
| 15 | 49407 |
| 16 | 3840 |
| 17 | 50687 |
| 18 | 431616 |
| 19 | 373759 |
| 20 | 721920 |
| 21 | 1062911 |
| 22 | 2308096 |
| 23 | 4476927 |
| 24 | 10022912 |
| 25 | 17686527 |
| 26 | 34758656 |
| 27 | 82264063 |
| 28 | 240107520 |
| 29 | 270499839 |
| 30 | 238256128 |
| 31 | 140836863 |
| 32 | 6443433984 |
| 33 | 4296933375 |
| 34 | 15554969600 |
[1,1,6,7,20,15,88,47,272,31,2016,63,1600,8575,384, 49407,3840,50687,431616,373759,721920,1062911, 2308096,4476927,10022912,17686527,34758656, 82264063,240107520,270499839,238256128,140836863, 6443433984,4296933375,15554969600] |