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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 576 |
| 3 | 1920 |
| 4 | 3264 |
| 5 | 5376 |
| 6 | 12096 |
| 7 | 19584 |
| 8 | 31680 |
| 9 | 70656 |
| 10 | 114240 |
| 11 | 184704 |
| 12 | 411840 |
| 13 | 665856 |
| 14 | 1076544 |
| 15 | 2400384 |
| 16 | 3880896 |
| 17 | 6274560 |
| 18 | 13990464 |
| 19 | 22619520 |
| 20 | 36570816 |
| 21 | 81542400 |
| 22 | 131836224 |
| 23 | 213150336 |
| 24 | 475263936 |
| 25 | 768397824 |
| 26 | 1242331200 |
| 27 | 2770041216 |
| 28 | 4478550720 |
| 29 | 7240836864 |
[0,576,1920,3264,5376,12096,19584,31680,70656, 114240,184704,411840,665856,1076544,2400384, 3880896,6274560,13990464,22619520,36570816, 81542400,131836224,213150336,475263936,768397824, 1242331200,2770041216,4478550720,7240836864] |