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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 60 |
| 4 | 93 |
| 5 | 140 |
| 6 | 429 |
| 7 | 620 |
| 8 | 893 |
| 9 | 2576 |
| 10 | 3689 |
| 11 | 5280 |
| 12 | 15089 |
| 13 | 21576 |
| 14 | 30849 |
| 15 | 88020 |
| 16 | 125829 |
| 17 | 179876 |
| 18 | 513093 |
| 19 | 733460 |
| 20 | 1048469 |
| 21 | 2990600 |
| 22 | 4274993 |
| 23 | 6111000 |
| 24 | 17430569 |
| 25 | 24916560 |
| 26 | 35617593 |
| 27 | 101592876 |
| 28 | 145224429 |
| 29 | 207594620 |
| 30 | 592126749 |
| 31 | 846430076 |
[0,9,60,93,140,429,620,893,2576,3689,5280,15089, 21576,30849,88020,125829,179876,513093,733460, 1048469,2990600,4274993,6111000,17430569,24916560, 35617593,101592876,145224429,207594620,592126749, 846430076] |