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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 27 |
| 5 | 108 |
| 6 | 270 |
| 7 | 540 |
| 8 | 945 |
| 9 | 1512 |
| 10 | 2268 |
| 11 | 3240 |
| 12 | 4455 |
| 13 | 5940 |
| 14 | 7722 |
| 15 | 9828 |
| 16 | 12285 |
| 17 | 15120 |
| 18 | 18360 |
| 19 | 22032 |
| 20 | 26163 |
| 21 | 30780 |
| 22 | 35910 |
| 23 | 41580 |
| 24 | 47817 |
| 25 | 54648 |
| 26 | 62100 |
| 27 | 70200 |
| 28 | 78975 |
| 29 | 88452 |
| 30 | 98658 |
| 31 | 109620 |
| 32 | 121365 |
| 33 | 133920 |
| 34 | 147312 |
| 35 | 161568 |
| 36 | 176715 |
| 37 | 192780 |
| 38 | 209790 |
| 39 | 227772 |
| 40 | 246753 |
[0,0,0,27,108,270,540,945,1512,2268,3240,4455, 5940,7722,9828,12285,15120,18360,22032,26163, 30780,35910,41580,47817,54648,62100,70200,78975, 88452,98658,109620,121365,133920,147312,161568, 176715,192780,209790,227772,246753] |