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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 225 |
| 3 | 825 |
| 4 | 3025 |
| 5 | 7315 |
| 6 | 17689 |
| 7 | 34713 |
| 8 | 68121 |
| 9 | 117711 |
| 10 | 203401 |
| 11 | 322465 |
| 12 | 511225 |
| 13 | 761475 |
| 14 | 1134225 |
| 15 | 1611345 |
| 16 | 2289169 |
| 17 | 3133423 |
| 18 | 4289041 |
| 19 | 5697321 |
| 20 | 7568001 |
| 21 | 9807315 |
| 22 | 12709225 |
| 23 | 16131625 |
| 24 | 20475625 |
| 25 | 25534575 |
| 26 | 31843449 |
| 27 | 39111633 |
| 28 | 48038761 |
| 29 | 58227331 |
[15,225,825,3025,7315,17689,34713,68121,117711, 203401,322465,511225,761475,1134225,1611345, 2289169,3133423,4289041,5697321,7568001,9807315, 12709225,16131625,20475625,25534575,31843449, 39111633,48038761,58227331] |