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| n | a(n) |
|---|---|
| 1 | 81 |
| 2 | 405 |
| 3 | 1215 |
| 4 | 2835 |
| 5 | 5670 |
| 6 | 10206 |
| 7 | 17010 |
| 8 | 26730 |
| 9 | 40095 |
| 10 | 57915 |
| 11 | 81081 |
| 12 | 110565 |
| 13 | 147420 |
| 14 | 192780 |
| 15 | 247860 |
| 16 | 313956 |
| 17 | 392445 |
| 18 | 484785 |
| 19 | 592515 |
| 20 | 717255 |
| 21 | 860706 |
| 22 | 1024650 |
| 23 | 1210950 |
| 24 | 1421550 |
| 25 | 1658475 |
| 26 | 1923831 |
| 27 | 2219805 |
| 28 | 2548665 |
| 29 | 2912760 |
| 30 | 3314520 |
| 31 | 3756456 |
| 32 | 4241160 |
| 33 | 4771305 |
| 34 | 5349645 |
[81,405,1215,2835,5670,10206,17010,26730,40095, 57915,81081,110565,147420,192780,247860,313956, 392445,484785,592515,717255,860706,1024650, 1210950,1421550,1658475,1923831,2219805,2548665, 2912760,3314520,3756456,4241160,4771305,5349645] |