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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 180 |
| 3 | 1444 |
| 4 | 12996 |
| 5 | 23805 |
| 6 | 36100 |
| 7 | 52020 |
| 8 | 60228 |
| 9 | 64980 |
| 10 | 68832 |
| 11 | 95220 |
| 12 | 301140 |
| 13 | 324900 |
| 14 | 344160 |
| 15 | 481824 |
| 16 | 1505700 |
| 17 | 1718721 |
| 18 | 1720800 |
| 19 | 2275758 |
| 20 | 2409120 |
| 21 | 3755844 |
| 22 | 6874884 |
| 23 | 6879645 |
| 24 | 7965153 |
| 25 | 8593605 |
| 26 | 11378790 |
| 27 | 12045600 |
| 28 | 15930306 |
| 29 | 17405892 |
[1,180,1444,12996,23805,36100,52020,60228,64980, 68832,95220,301140,324900,344160,481824,1505700, 1718721,1720800,2275758,2409120,3755844,6874884, 6879645,7965153,8593605,11378790,12045600, 15930306,17405892] |