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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 20 |
| 3 | 105 |
| 4 | 336 |
| 5 | 825 |
| 6 | 1716 |
| 7 | 3185 |
| 8 | 5440 |
| 9 | 8721 |
| 10 | 13300 |
| 11 | 19481 |
| 12 | 27600 |
| 13 | 38025 |
| 14 | 51156 |
| 15 | 67425 |
| 16 | 87296 |
| 17 | 111265 |
| 18 | 139860 |
| 19 | 173641 |
| 20 | 213200 |
| 21 | 259161 |
| 22 | 312180 |
| 23 | 372945 |
| 24 | 442176 |
| 25 | 520625 |
| 26 | 609076 |
| 27 | 708345 |
| 28 | 819280 |
| 29 | 942761 |
| 30 | 1079700 |
| 31 | 1231041 |
| 32 | 1397760 |
| 33 | 1580865 |
| 34 | 1781396 |
| 35 | 2000425 |
[0,1,20,105,336,825,1716,3185,5440,8721,13300, 19481,27600,38025,51156,67425,87296,111265,139860, 173641,213200,259161,312180,372945,442176,520625, 609076,708345,819280,942761,1079700,1231041, 1397760,1580865,1781396,2000425] |