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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 12 |
| 3 | 175 |
| 4 | 2448 |
| 5 | 34481 |
| 6 | 485100 |
| 7 | 6826079 |
| 8 | 96049728 |
| 9 | 1351523425 |
| 10 | 19017374892 |
| 11 | 267594778639 |
| 12 | 3765344259600 |
| 13 | 52982414452241 |
| 14 | 745519146496332 |
| 15 | 10490250465629375 |
| 16 | 147609025664755968 |
| 17 | 2077016609773544641 |
| 18 | 29225841562491165900 |
| 19 | 411238798484657629039 |
[0,1,12,175,2448,34481,485100,6826079,96049728, 1351523425,19017374892,267594778639,3765344259600, 52982414452241,745519146496332,10490250465629375, 147609025664755968,2077016609773544641, 29225841562491165900,411238798484657629039] |