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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 48 |
| 5 | 50 |
| 6 | 360 |
| 7 | 735 |
| 8 | 2240 |
| 9 | 2268 |
| 10 | 25200 |
| 11 | 25410 |
| 12 | 332640 |
| 13 | 334620 |
| 14 | 336336 |
| 15 | 675675 |
| 16 | 11531520 |
| 17 | 11571560 |
| 18 | 220540320 |
| 19 | 221152932 |
| 20 | 221707200 |
| 21 | 222211080 |
| 22 | 5121436320 |
| 23 | 5131136010 |
| 24 | 25700298624 |
| 25 | 25741485000 |
| 26 | 77338861600 |
| 27 | 77445096300 |
| 28 | 2248776129600 |
| 29 | 2251453244040 |
[1,4,9,48,50,360,735,2240,2268,25200,25410,332640, 334620,336336,675675,11531520,11571560,220540320, 221152932,221707200,222211080,5121436320, 5131136010,25700298624,25741485000,77338861600, 77445096300,2248776129600,2251453244040] |