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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 132 |
| 3 | 87516 |
| 4 | 140229804 |
| 5 | 396499770810 |
| 6 | 1671643033734960 |
| 7 | 9490348077234178440 |
| 8 | 67867669180627125604080 |
| 9 | 583692803893929928888544400 |
| 10 | 5838544419011620940996212276800 |
| 11 | 66244124978105851196543024492572800 |
| 12 | 836288764382254532915188713779640302400 |
| 13 | 11570895443447601081407359451642915869302000 |
[1,1,132,87516,140229804,396499770810, 1671643033734960,9490348077234178440, 67867669180627125604080, 583692803893929928888544400, 5838544419011620940996212276800, 66244124978105851196543024492572800, 836288764382254532915188713779640302400, 11570895443447601081407359451642915869302000] |