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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 10 |
| 4 | 70 |
| 5 | 105 |
| 6 | 2310 |
| 7 | 5460 |
| 8 | 20020 |
| 9 | 340340 |
| 10 | 6466460 |
| 11 | 461890 |
| 12 | 37182145 |
| 13 | 106234700 |
| 14 | 25160850 |
| 15 | 55454513400 |
| 16 | 1719089915400 |
| 17 | 573029971800 |
| 18 | 4011209802600 |
| 19 | 148414762696200 |
| 20 | 148414762696200 |
| 21 | 196290492598200 |
| 22 | 261655226633400600 |
| 23 | 392482839950100900 |
| 24 | 18446693477654742300 |
| 25 | 64563427171791598050 |
[1,1,10,70,105,2310,5460,20020,340340,6466460, 461890,37182145,106234700,25160850,55454513400, 1719089915400,573029971800,4011209802600, 148414762696200,148414762696200,196290492598200, 261655226633400600,392482839950100900, 18446693477654742300,64563427171791598050] |