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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 285 |
| 3 | 2010 |
| 4 | 8790 |
| 5 | 28785 |
| 6 | 77595 |
| 7 | 181860 |
| 8 | 383580 |
| 9 | 745155 |
| 10 | 1355145 |
| 11 | 2334750 |
| 12 | 3845010 |
| 13 | 6094725 |
| 14 | 9349095 |
| 15 | 13939080 |
| 16 | 20271480 |
| 17 | 28839735 |
| 18 | 40235445 |
| 19 | 55160610 |
| 20 | 74440590 |
| 21 | 99037785 |
| 22 | 130066035 |
| 23 | 168805740 |
| 24 | 216719700 |
| 25 | 275469675 |
| 26 | 346933665 |
[15,285,2010,8790,28785,77595,181860,383580, 745155,1355145,2334750,3845010,6094725,9349095, 13939080,20271480,28839735,40235445,55160610, 74440590,99037785,130066035,168805740,216719700, 275469675,346933665] |