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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 672 |
| 3 | 3120 |
| 4 | 7800 |
| 5 | 11904 |
| 6 | 23712 |
| 7 | 55552 |
| 8 | 195072 |
| 9 | 302784 |
| 10 | 492864 |
| 11 | 910336 |
| 12 | 1607808 |
| 13 | 1671072 |
| 14 | 1750656 |
| 15 | 6688560 |
| 16 | 13210368 |
| 17 | 15242496 |
| 18 | 16125952 |
| 19 | 16721400 |
| 20 | 17033984 |
| 21 | 17274624 |
| 22 | 26854656 |
| 23 | 56755968 |
| 24 | 633404992 |
| 25 | 805208064 |
| 26 | 874527872 |
| 27 | 904786944 |
| 28 | 1524577280 |
| 29 | 2059528512 |
| 30 | 2226866176 |
[1,672,3120,7800,11904,23712,55552,195072,302784, 492864,910336,1607808,1671072,1750656,6688560, 13210368,15242496,16125952,16721400,17033984, 17274624,26854656,56755968,633404992,805208064, 874527872,904786944,1524577280,2059528512, 2226866176] |