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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 4 |
| 2 | 20 |
| 3 | 48 |
| 4 | 160 |
| 5 | 320 |
| 6 | 960 |
| 7 | 1792 |
| 8 | 5120 |
| 9 | 9216 |
| 10 | 25600 |
| 11 | 45056 |
| 12 | 122880 |
| 13 | 212992 |
| 14 | 573440 |
| 15 | 983040 |
| 16 | 2621440 |
| 17 | 4456448 |
| 18 | 11796480 |
| 19 | 19922944 |
| 20 | 52428800 |
| 21 | 88080384 |
| 22 | 230686720 |
| 23 | 385875968 |
| 24 | 1006632960 |
| 25 | 1677721600 |
| 26 | 4362076160 |
| 27 | 7247757312 |
| 28 | 18790481920 |
| 29 | 31138512896 |
| 30 | 80530636800 |
| 31 | 133143986176 |
| 32 | 343597383680 |
[0,4,20,48,160,320,960,1792,5120,9216,25600,45056, 122880,212992,573440,983040,2621440,4456448, 11796480,19922944,52428800,88080384,230686720, 385875968,1006632960,1677721600,4362076160, 7247757312,18790481920,31138512896,80530636800, 133143986176,343597383680] |