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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 3 |
| 2 | 20 |
| 3 | 87 |
| 4 | 264 |
| 5 | 635 |
| 6 | 1308 |
| 7 | 2415 |
| 8 | 4112 |
| 9 | 6579 |
| 10 | 10020 |
| 11 | 14663 |
| 12 | 20760 |
| 13 | 28587 |
| 14 | 38444 |
| 15 | 50655 |
| 16 | 65568 |
| 17 | 83555 |
| 18 | 105012 |
| 19 | 130359 |
| 20 | 160040 |
| 21 | 194523 |
| 22 | 234300 |
| 23 | 279887 |
| 24 | 331824 |
| 25 | 390675 |
| 26 | 457028 |
| 27 | 531495 |
| 28 | 614712 |
| 29 | 707339 |
| 30 | 810060 |
| 31 | 923583 |
| 32 | 1048640 |
[0,3,20,87,264,635,1308,2415,4112,6579,10020, 14663,20760,28587,38444,50655,65568,83555,105012, 130359,160040,194523,234300,279887,331824,390675, 457028,531495,614712,707339,810060,923583,1048640] |