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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 30 |
| 3 | 285 |
| 4 | 1496 |
| 5 | 5525 |
| 6 | 16206 |
| 7 | 40425 |
| 8 | 89440 |
| 9 | 180441 |
| 10 | 338350 |
| 11 | 597861 |
| 12 | 1005720 |
| 13 | 1623245 |
| 14 | 2529086 |
| 15 | 3822225 |
| 16 | 5625216 |
| 17 | 8087665 |
| 18 | 11389950 |
| 19 | 15747181 |
| 20 | 21413400 |
| 21 | 28686021 |
| 22 | 37910510 |
| 23 | 49485305 |
| 24 | 63866976 |
| 25 | 81575625 |
| 26 | 103200526 |
| 27 | 129406005 |
| 28 | 160937560 |
| 29 | 198628221 |
| 30 | 243405150 |
[1,30,285,1496,5525,16206,40425,89440,180441, 338350,597861,1005720,1623245,2529086,3822225, 5625216,8087665,11389950,15747181,21413400, 28686021,37910510,49485305,63866976,81575625, 103200526,129406005,160937560,198628221,243405150] |