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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 120 |
| 4 | 3876 |
| 5 | 376992 |
| 6 | 119877472 |
| 7 | 131254487936 |
| 8 | 509850594887712 |
| 9 | 7145544812472168960 |
| 10 | 364974894538906616240640 |
| 11 | 68409601066028072105113098240 |
| 12 | 47312269462735023248040155132636160 |
| 13 | 121317088003402776955124829814219234385920 |
[1,2,10,120,3876,376992,119877472,131254487936, 509850594887712,7145544812472168960, 364974894538906616240640, 68409601066028072105113098240, 47312269462735023248040155132636160, 121317088003402776955124829814219234385920] |